Pretty much any SV build is going to be better than MM or BM at the moment. With the changes they made in the last significant patch SV abilitys just scale a lot better than the others now. They did make some changes to put them closer together but SV still comes out on top. There is math out there to support this but I am sure you and most people already just know that it is true.

(When I refer to a spreadsheet I am talking about "Shandaras WotLK Spreadsheet". It has been used and trusted by the best theorycrafting hunters for a long time. In my opinion its a great tool so thats why I use it. It is not blind loyalty though. I like it to make sense to me.)

As far was mine being the best SV one. I put my gear into the spreadsheat and set up a 6/14/51 vs 1/18/52 build and 6/14/51 was better. I was sold on 6/14/51 before that though. The "soft cap" for haste is 522 which gives 1.5s steady shots. I have 354 haste right now. Using the 5/5 IAotH eliminates that problem pretty well. Then the focused fire is just 1% extra damage. In my opinion I don't have the haste to pull off at 1/5 IAotH build. Serpent Stings damage itself is not a huge part of the overall damage. So buffing it by 30% + aimed shot is not doing enough to overcome 5/5 IAotH and Focused Fire.

6/14/51 is also the spec used to produce highest possible hunter dps as well when factoring in JC and best in slot gear according to the spreadsheet.

As a strength the 5/5 IAotH is always a white dps increase. Most of what I said above is what I consider the strengths of the build.
As a weakness I suppose multi having a .5s cast and not being a true instant could be situationally harmful.
If you are very, very unlucky and never got hawk procs then it could be a waste of points.
Could see sniper training being a weakness as well if you cannot stay in buff range.
As a strength/weakness your pet gains a little bit more importance. A 1% more damage importance. Could be a weakness if you cannot keep it alive but a strength if you can.

I'm not trying to say my spec is the be all end all of hunter specs. I think you should always play with what you feel most comfortable in. Personal choice plays a significant role in specs and whatever works best for you will be the best spec. This one just happens to be my favorite for the reasons I stated.

As far as rotation. I use a priority list. Killshot>Serpent Sting>Explosive>Multi>Steady.
Killshot is off GCD so it doesn't hurt rotation to use it. Serpent Sting should be up as close to 100% as possible because of glyphs and Noxious talent. Explosive because its the staple shot. Multi because it scales far better than steady. Then steady to fill the space between Explosive cooldown.
Its not a set in stone order. The shots are not always fired in a specific order. Movement and haste buffs change it a bit. The main idea is to fire Killshot whenever possible, use Explosive on every cooldown without ever delaying it, and keeping Serpent Sting up

With LnL procs it changes of course. In order- Explosive->Multi->Explosive->pause-> Explosive.
The pause is to prevent overwriting the debuff and losing a tick. Sometimes replace the pause with a Serpent Sting refresh, Hunters Mark refresh or a hasted Steady Shot. It is situational.
I do like dropping frost traps to get free LnL procs but I am not a fan of trap dancing. Its not very practical and its hard to pull off correctly.
Kill Command every minute as well.
I have Power Auras running to help keep track of cooldowns and procs. Sometimes it gives me a headache though and I turn it off. So I don't rely on it too heavily.
I hope I explained that in a way that made sense.

For 3.1 been toying around with: http://ptr.wowhead.com/?talent=cZ0eVoZx0ci0cIhedAhsu
Trap mastery for Black Arrow damage. Resourcefulness for Black Arrow cooldown. Hunting Party is a lot better now. Sniper Training is still kinda iffy. Have to play with it more to see if it is any good. Rotation looks mostly the same with Black Arrow taking on the same importance as Serpent Sting. Theres no IAotH though. I can't find something to drop that makes it seem worth it. No Hawk Eye is not a big deal to me.
It is kind of hard to nail down something on this PTR. Seems they change it up every week. Still a work in progress though. I have PTR client that I have been trying things out on and keeping up with discussion. Going to try a new BM build too. They should be scaling pretty decent now.

I am really not good at explaining things. If you or anyone else needs more clarification I would be happy to add to it.