http://www.swtor.com/community/showthread.php?t=624205
Translated commando version of the guide above (start from the skill tree section)

I. Skill Tree
Gunnery 2.0 PVE spec 4/36/4

New talents for 2.0:

Quote :

Advance The Line (1pt): Increases the duration of Hold The Line (new ability explained in next section) by 4s.

Quote :

Overclock (2pts): Reduces the cooldown of Concussion Round by 7.5/15s and Tech Override by 15/30s. In addition, Tech Override has a 50/100% chance to yield a second charge, making your next two abilities with an activation time activate instantly.

Quote :

Decoy (2pts): Diversion has a 50/100% chance to intercept and absorb the next incoming direct Force or tech attack. Lasts 6/12s.

Quote :

Reflexive Shield (2pts): When you take damage, you have 50/100% chance to reduce the active cooldown of Reactive Shield by 1.5/3s. This effect cannot occur more than once every 1.5s. In addition, when taking damage, you have a 10/20% chance to emit an Energy Redoubt, which absorbs a low amount of damage and lasts 6/12s. This effect cannot occure more than once every 10s.

Quote :

Charged Launcher (3pts): Increases the damage dealt by High Impact Bolt, Grav Round, Demolition Round and Electro Net (new ability explained in next section) by 2/4/6%.

Note:

*I choose to put my 2 "elective" points in Tenacious Defense to reduce the cooldown of our CC breaker Tenacity. However I could see situations where Decoy or Concussive Force could be viable in certain encounters.

II. Gear & Stats Goals

Gear

Quote :

Set Bonus: Set bonuses are now exclusively carried by the armoring and no longer by any shells, i.e. Tionese/Columi/Rakata shells. You have two options here:

Option 1: 90% of mercs/commando will benefit from sticking with the old 4pc Dread Guard set bonus, which grants -8 energy cells cost to High Impact Bolt. This is what everyone is used to from 1.7 and will still allow for a very good dps output. Expecially since it makes heat management tremendously easier. This is the option I have chosen for now.

Option 2: If you don't have your old 4pc DG set or if you want to sport all Kell Dragon gear, the new 4pc which grants 8% damage increase to Hight Impact Bolt is your other option. This is quite viable way to go just requires paying more attention to heat and mixing in more Hammer Shot fillers.

Both of these options can result in similar dps output, just different styles. But remember, the less you have to think about during a boss fight, the better you're going to perform.

BiS Augments: Advanced Reflex Augment 28
BiS Relics: Kell Dragon Relic of the Serendipitous Assault & Underworld Relic of Boundless Ages

Stats: Aim = Accuracy (99.95/109.95%) > Crit (240 rating) > Power > Surge (72.01%) > Alacrity

Quote :

Accuracy: Goal = 430 rating = 99.95/109.95%. Get this to at least 99/109% before worrying about Surge.
Surge: Goal = 430 rating = 72.01%
Power/Crit: The sweet spot for crit seems to be right around 240, this could be gained a number of ways through mods/enhances/ear/implants...the easy way IMO is 2 mods/2 enhances with all the crit pieces that drop in current operations. This would leave you with 1310 Power

Detailed BiS Gear Sheet:
http://tinypic.com/view.php?pic=3131x5y&s=5

III. Abilities & Priority System

We get two new abilities in 2.0; one offensive, one defensive. This section is all about offense, and 2.0 has brought Electro Net into our rotation to be used on cooldown (every 1m30s). This is a handy DPS burst ability by way of DoT and should be used on cd following any higher priority abilities listed in the priority system section.

New to 2.0:

Quote :

Electro Net
Instant
Cooldown: 1m30s
Fires an electro net that ensnares the target, reducing its movement speed by 50% and dealing energy damage over 9 seconds. The damage dealt by the electro net increases by 20% for every second that the remains moving. This effect stacks up to 10 times on enemy players or up to 5 times on any other target. Additionally, the electro net hinders the target, preventing the use of high mobility actions and escapes such as charges, vanishes and speed boosts. Lasts 9 seconds

Note:
*This ability doesn't act the same on NPCs as it does actual players in PVP. It doesn't matter if an NPC is moving or not, it will place a 10 tick DoT on the target, ticking once per second. The 2nd-6th ticks will increase in damage from the previous tick by 20%. The 7th-10th ticks will be identical to the 6th tick.

Commandos follow a priority system based on damage and energy cells cost. Our energy cells regeneration is greatest (5 cells/s) when we stay between 60-100 energy cells. Therefore, you should do your best to always stay above 60 cells (also be careful not to allow your energy cells to reach 100 for more than an instant) unless the situation allows you to burn. This could be the end of a fight, or a time within the fight where you know a short break of dps is coming up where your energy cells will have time to regenerate. You should ALWAYS burn the target (ignore hammer shots) when your Recharge Cells ability cd<~10s; this includes your opening sequence. The only exceptions are situational, usually the end of a boss fight when you'll need to be going all out. In these cases, wait on using Recharge Cells if you'll need it before the two minute cd is over.

Spoiler:

Now we have 3 major changes in 2.0. First, High Impact Bolt is no longer free (costs 2 or 10 energy cells depending on set bonus) but still efficient. Second, Electro Net (costs 8 energy cells) is our added ability that comes off cd every 1m30s. 3rd, you're now only going to need one GR to gain the 25% damage boost to DR as well as 20% armor debuff instead of three. The armor debuff will now last 45s. This effect works the same as the gunslinger's flourish shot now.

Single Target Priority:

Notes:

*Tech Override, Mortar Volley  and Plasma Grenade are situational, i.e. you usually want to save Tech Override for using casted abilities on the move instead of wasting it in stand still position (but on a dummy use it to open and when your heat is going to hit 0)...or adds are prominent in the fight where MV or Reserve Power Cell(RPC)+ Plasma Grenade would be better used for AoE rather than single target.

*I am combining priority system for both 4pc set bonus options. The only real difference is that with the new 4pc, you'll want to make sure you get a minimum of 4 Charged Barrel before using High Impact Bolt. With new 4pc you should also be weary of High Impact Bolt when below 76 energy cells since technically you won't want to use it below 70 energy cells, but just be aware of your energy cells when it's coming off cd so you can fire it at will along with DR. With the old 4pc, just use High Impact Bolt on cd when your energy cells is below than 83, you can build up Charged Barrel if you like, it won't make a great deal of difference either way, I take it situationally if I think I can squeeze in another Grav Round without messing up my flow I will do so.

Opening Burst
There are a lot of quality openers you can use, I encourage you to experiment with them. This is the one I've found to work best for me.

1. Tech Override + Grav Round (Only use TO on dummies and specific fights where you won't need to move for a while)
2. Relic/Adrenal
3. High Impact Bolt
4. Demolition Round
4. Electro Net
5. Full Auto (if Curtain of Fire proc'd)
6. Grav Round
7. Proceed with Priority System using Mortar Volley & RPS + PG situationally

With no more need for multiple Grav Rounds to get the armor debuff and damage gain to DR, there's no need to open with multiple Grav Rounds. High Impact Bolt is now the only ability that relies on multiple Grav Rounds and should be used after getting 4 Charged Barrels (2 Grav Rounds will do the trick)

2.0 Priority System

Energy Cells < 76: High Impact Bolt > RPC + PG > Hammer Shots
76 < Energy Cells < 83: High Impact Bolt > DR > EN > RPC + PG > FA > GR
Energy Cells > 83: DR > EN > FA > TO + GR

*Should also be used when DR/FA cd=<1.5s and energy cells is at or below 80 (as well as High Impact Bolt - 4 charged barrel minimum if using new 4pc).

**You can use Mortar Volley in single target situations when AoE is not needed for at least the next 60s. For maximum dps it should be used right after a curtain of fire proc'd FA when all other abilities are on cd. You can fire off hammer shots beforehand if your energy cells is below 80.

Note: We aren't the most mobile class, we put out much more damage when we can turret down our target. But if DR and High Impact Bolt are on cd when you need to move and your energy cells is sitting fine so you don't want to spam hammer shots. Consider using Sticky Grenade>Explosive Round while on the move and your energy cells is high. I like to rotate between those and hammer shots in these situations. Also, you could throw in a TO+GR or TO+RPC+PG so they can be used on the run

Multiple Target Priority:

Commandos have beastly AoE damage and the priority system is as follows:

1. Mortar Volley
2. Pulse Cannon
3. *RPC+PG
3. Hail of Bolts

*You don't necessarily have to use PG with RPC. It does produce higher DPS, but isn't as energy cells efficient, so if you're not worried about energy cells, use it without RPC if you like. But unless you're going to get some downtime after your burn, I would wait for RPC.

Also, while you're running up to the mob you want to annihilate or waitiing for them to position themselves in a nice pile for you, throw an Sticky Grenade OR Plasma Grenade (with or without RPC depending on asterick'd note above) in there for a bit extra delayed AoE damage.

IV. Tips & Tricks

Action Queue

Quote :

First thing you need to do as a Commando is turn on the "Ability Action Queue Window" and set it to 1s. This is found in Preferences>Controls. You should be utilizing this by queing nearly every ability throughout your "rotation" to minimize delay between actions. This will help maximize DPS.

Don't miss out on Curtain of Fire proc!

Quote :

Neat trick you can utilize when fishing for a Curtain of Fire proc while spamming Grav Round. It only pertains to the situation when all high priority abilities' cd>1.5s, your next GR would result in energy cells>76 (or recharge cells cd<~10s), and you're fishing for a Curtain of Fire proc:

1. Press hotkey for GR
2. Press hotkey for FA during cast of GR
3. Immediately after GR cast is finished, tap hotkey for GR

When step 3 is timed properly, it allows for 2 things:

A. FA to cast immediately if Curtain of Fire procs.
B. GR to cast again with minimal delay if Curtain of Fire doesn't proc.

The benefit of A outweighs the minimal delay from B.

Note:

* If you experience a lot of lag, this technique may not be possible. If you time step 3 a bit off, you could end up interrupt Full Auto, wasting a proc and a GCD. With practice and no lag, you should be fine. Instead of using this, some people will double cast GR and step out of it into an Full Auto when they see the proc. They can both be effective, I like the former personally.

Anticipate

Quote :

You need to be thinking ahead at least 1 or 2 abilities. See what's coming off cd soon, see where your energy is. You need to be able to anticipate what your energy is going to be by the time your "next" ability fires. For instance, when I'm casting GR, I'm looking at the energy, at the very last split second, I look to see if my energy is dropping into 90+...if it is, then I know my energy will be >76 when it finishes and I know I'm free to spam whatever ability is highest on priority list next. If not, I know I may need to queue a hammer shots filler.

This goes for other situations as well, anticipate when you're free to "burn" the target ignoring energy costs, know when a target switch is coming up. This all comes with practice and familiarizing yourself with the operations and programming your muscle memory.

All credits go to odawgg.

This is actually really useful to me. I'm currently leveling my Trooper and just finished Balmorra. I'm probably going to FP/WZ/SCM grind to 40 before I do Hoth, but this will help me with my endgame.

~D

Updated.

Thanks for the update, I'll be looking at this when I get my Commando up there. One question though, why divide your final two points between First Responder in Medic and Weapon Calibrations in Assault? Wouldn't it be more beneficial to only invest in one of those two for the maximum benefit?

First Responder proc very often even with only 1 point in it.
FR+WC : 4% alacrity increase in average
2 FR: 3% alacrity
2 WC: 2% alacrity

Updated the link , didn't know it was the wrong one ..