I agree with the person that said play the race YOU want to play, not the race others want you to play. More people on Alliance for arenas and stuff, but shorter queue times on Horde. Toss a coin if you must, but just remember that whatever you choose, you're the one who has to stare at your character's backside from here to eternity, no one else.
it does but you need a paid account for RAF to work thats how i lvl'd my sham to 20 in like a few hours...
and i would reccomend horde just because there are far too many alliance and we have 1-2 min queues but again like everyone else said Pick the class you want to play