Top DPS as a Hunter : Marksmanship

As we all know the main DPS specs in WOTLK are Marksmanship & Survival , many guys who are just into numbers (thankfully xD) started to write spreadsheets to simply show you if you are gemmed correctly and your rotation and stuff are the best to maximize you DPS as much as possible.

Yet , the top DPS spec is shown to be Marksmanship compared to Survival , specially when you are close to Armor Penetration Cap which is

You may wonder what should i gem , Agility vs Armor Penetration . If you are a survival , you just dont need to worry about Armor Penetration , because survival relays on high Agility for a high chance to crit and more attack power .

As Marksmanship , you could start to gem ArP only and if only you are into the area of Passive ArP , Passive ArP means the ArP you get only from your gear without any gems or procs.

So here is the list of when you will need to start gemming ArP depending on your Passive ArP :

1- (0~400 ArP) - You can still be Survial / Marksmanship , wont be a big difference, keeping gemming agility.
2- (400~700 ArP) - You can be Marksmanship and safely drop Improved Arcaneshot from your talent , and remove it from your rotation , but you still continue gemming agility. you can use the talent points spent on Imp Arcanshot on Improved Hunter Mark.

Upon reaching 720~780 , you can get a trinket with ArP increasing Proc , this is called Softcap , you can find one of the trinkets in ulduar 25 (Mjolnir Runestone) .

For hard cap , you will need to make sure that your gear gives you around 800 ArP , so you make sure you have enough good gear which wont let you lose lot of Attack Power and Critical Chance.

-Your rotation when 0~400 ArP should be like this :
Rapid Fire > Kill Shot > Silencing Shot > Serpent Sting > Chimera Shot > Aimed Shot > Ready Shot > Arcane Shot >Steady Shot

-Your rotation upon getting 400~700 or more ArP should be like this :
Rapid Fire > Kill Shot > Silencing Shot > Serpent Sting > Chimera Shot > Aimed Shot > Ready Shot > Steady Shot

Hint: if you are ArP capped , and when you are in a raid , try keeping one Rapid Fire for the time when a Shaman pops heroism , so when the shaman does it , pop your Rapid Fire!, your Steady Shot cast time may become 0.9 sec or less (depends on your haste) .. so start spamming Steady Shot , and go back to your normal rotation after Rapid Fire effect expires , you will notice that this period will increase your overall DPS by a nice amount .

Links:
http://www.femaledwarf.com (Zeharah's Hunter DPS Analyzer)