Why this build
How the build works
This Marksmanship Hunter build stacks crit and then makes each crit worth more. Lethal Attacks adds 5% crit chance to all your attacks, and Mortal Shots raises the crit damage bonus of your ranged abilities by 30%.
Careful Aim is the other half: at 5/5 it adds Attack Power equal to 100% of your Intellect. Intellect is no longer just a mana stat for you, and mail with Intellect becomes a real damage upgrade.
Efficiency cuts the mana cost of your shots, stings and melee abilities by 9% at 3/5. Rapid Killing takes 2 min off Rapid Fire’s cooldown, and when a non-trivial enemy dies with your Serpent Sting on it, your next shot within 20 sec deals 20% more damage. Trueshot Aura, the 21st point, gives the whole party 15 Ranged Attack Power.
Leveling tips
Lethal Attacks fills levels 10 to 14 and Careful Aim levels 15 to 19. Efficiency follows, then Rapid Killing at 23 and 24, and Mortal Shots from 25. Trueshot Aura comes last at 30.
Rapid Killing rewards chain-pulling: keep Serpent Sting on every target and you start each new fight with a stronger opener. Mana is the main limit while leveling, so drink when you need to and keep Efficiency.
You can still level with a pet as Marksmanship; it tanks and adds damage. Beast Mastery is the easier solo choice, but Marksmanship becomes more attractive in dungeons. These Hunter talents also make a good base for a level 60 Marksmanship build.
Changes in WoW Forever
Careful Aim, Rapid Killing, Lone Wolf and Rapid Recuperation are new talents. Trueshot Aura moved higher in the tree, and the 28 Oct hotfix cut it to 15 Ranged Attack Power at level 30 and also reduced the Ranged Attack Power from Aspect of the Hawk. Sniper Shot is the new bottom talent: a long-range shot that also extends the range of your next 3 shots by 10 yards.
Toward level 60
Provisional. Two level 60 builds exist and they disagree. One guide goes almost pure Marksmanship (5 in Beast Mastery for Deadly Aspects, the rest down to Sniper Shot). A simulator prefers about 31 in Marksmanship with 15 in Survival. Both take Lone Wolf, Ranged Weapon Specialization and Sniper Shot. Confidence is medium.