Arabia looks strong. Camel archers look like an early candidate for special unit MVP of the game if you ask me. And the middle ages usually end up being violent for me, we'll see if this trend continues in civ V. Then special marketplace, commerce bonuses and +oil are candy on top.
I like the look of Ottomans for mid game conquesting. I'll have to wait to play test, but Janissary full heal on victory could be nothing short of awesome for sustaining a difficult invasion into enemy territory with 1 UPT. Juries still out on whether the UA will be useful, though.
Persia seems like one of the more flexible civs. I could imagine them being an early rusher, or as a builder/science oriented civ. Depends a lot on their UB, and how many golden ages its possible to get.
Hmm I'm noticing a theme in my list. I usually like the middle eastern city/art styles, lol.