[Figgs]

I'm thinking all three will be very viable and fun, as long as you're not a fresh 70 stepping into Northrend. With the small itemization gap, most players will be out-gearing the first few zones.

With that in mind, I'm thinking Affliction may have an edge in collection type and mass-kill type quests.

There's also the rep grinds to consider. I'm not sure how it is on Beta at the moment, but there seems to be quite a few less factions to go for. Still, there may be a point to instance grinding so we can get a good head-start on rep. I'd probably go Demonology or Destruction for instance grinding.

But probably just Affliction, because I love Affliction. :P