I haven't had a lot of time to play (still only level 63), but I've made it to Shattrath City and seen the whole Aldor/Scryer faction debate.
It's a pretty neat idea, acutually, having two opposing factions, and having your choice be meaningful. However, the execution of making that choice could have been improved.
As far as I could see, you go to Shattrath City, take the tour, and then are presented with the choice of which faction to join almost immediately. I found that I simply didn't have enough information to make a choice that I was happy with. All I knew was that Aldor = draenei and Scryer = blood elves. So I went with Aldor. I didn't really see any other place you could find out more.
I'm sure that you could have looked up the rewards online, and picked a faction that way, but that seems very clinical to me.
What Blizzard should have done is have a couple quests where the two factions are actively trying to woo you to their side. I'd go with two quests for each side (four total). One quest shows the good side of the faction, and the other quest shows the dark side of the faction. Rep changes would be fairly minimal to allow people to "taste" each faction.
Then, after doing these initial quests, you could make a meaningful, and more permanent, choice.