[This was a response of mine for another thread, and I thought people might find it useful]
ALSO: I entered inferno AFTER the nerf to smoke screen. I had the 5 second smoke screen for nightmare/hell, but quite honestly, I used it the same I use it now, to dodge an attack <1 second before it hits.
This is the build I use to farm Act 1 (Cursed Hold quest starting point -> Butcher, and I make sure I have 5 NV stacks before the Warden, as he will drop 2-3 rares with 100% MF, usually)
My bow is 900 DPS, and my attack speed is 2.2.
Health: 27k (14% HP from helm socket, and +68 vitality from sockets on my pants)
Armor: 2600-3000 (Depending)
To get that IAS, I have 15% IAS on both of my rings (With 70 dex, as these rings are cheap, and cost effective.) And my gloves are 110 Dex/15% IAS. These 3 pieces are all <150k combined.
When searching for gear in the AH, set the 3 filters to;
-All Resist 25-50 (Depending on budget)
-Dex 75-125 (Depending on your budget)
-Vitality 35-75 (Depending on budget)
Pay attention to how much armor these pieces have, and what you are paying for. Don't pay extra for useless stats you don't need.
Set the max buyout to 200k, if you get no results increase by 50k and check again, sort by minimum buyout and go to town. Thats I've done to get to a point where I can farm Act 1 Inferno.
NOTE: I use the increased movement speed for kiting, it works EXTREMELY well, and I pop MFD whenever there is an elite pack, or anyone that wont drop in 4 seconds. Ive tried other abilities that use hatred or discipline, and for my personal style, I dislike having to use Discipline for anything other than SS/MFD. http://us.battle.net/d3/en/calculator/demon-hunter#aRjTXV!Tea!YcYZac
I have 161% Crit Damage, and a base crit chance of 5%. to achieve this (Without a bow) I have a radiant square emerald on my weapon (60%+) and I have an amulet with 51% crit damage.
Whenever I find an elite pack I back off, clear as many normal mobs as I can, then look on my map to find a kiting path. Kiting path=circular path that you can infinitely run around.
When I am a safe distance away (From mortars/jailing/etc) I spam nether tentacles as much as I can before backing off. I use smokescreen for the 95% movement speed between the rune and my passive to gain distance, and do it again. Depending on the pack I will also staggershot 1-2 left clicks as I kite.
For the actual butcher fight, you have to be able to time all of his abilities. Learn when they trigger (Most of them are related to the time between attacks and the distance between you and him.) Smoke screen at the last possible moment to dodge the damage, and let your templar keep him occupied while you shoot a string of 10-15 elemental arrows. Keep on doing this while dodging the floor fire.
Depending if I mess up my smoke screen timing and when backup plan procs, I get bad positioning with the floor and I will get insta-killed by the fire, or by dodging the floor I have to walk into one of the butchers attacks without smokescreen. It's inferno, it happens. On average I will die 1-2 times each butcher fight, but I've also gone 3 runs in a row without dying. Warning: Your templar will have a hard time attacking the butcher if you dont have good gear on him. My templar has 2k armor and 60k hp.Feel free to add me if you want any advice or have any questions.