6:00 AM? Ahh, yes, I remember the days I could do that. Just last Saturday, in fact. Kind of fuzzy now, but I do, more or less, remember.

Who do I play most? Americans, by a long shot. They're a sentimental favorite, though if I had less on my to-do list, I might make Teddy Roosevelt or George Washington leader heads (nothing against Honest Abe, though)...
I've played other Civs just to test the game-play benefits of each "trait." The Persians were pretty good, but the Immortal was so dang good by itself, I was afraid it might've skewed the the game.
Right now (or at least last night), I'm playing the Germans on ZEB's Earth (huge) right now... but I have to step around some rule mods (and I'm not entirely sure what they are).
What little I've gleaned in the past few months:
*So far, the Industrious trait is a favorite.
*Commercial was weak. The extra commerce (that I remember) wasn't that significant, neither was the supposed drop in corruption. I think, when the editor comes out (it's still coming out, right?), that I'll have to make some adjustments to reduce corruption (maybe that should be a new thread).
*Militaristic: Unit promotions haven't exactly taken off. Of course, I've been playing with the random seed preserved, so I haven't been able slap fate around into coughing up some better luck. That said... the unit promotions in militaristic *seem* about average. Bummer.
*Scientific: *Slightly* cool with the extra advances, but they don't come so often as to make the quality a significant force in the average game (IME).
*Expansionist: Like the scout at the beginning, if only to figure out optimal placement for the next city (especially important if following the Rapid Expansion Strategy). I like the better goodies from goody huts, too, but how this quality plays really depends on the map you get dropped on. The smaller it is, and the closer the competition, the less effective it is. If you're expansionist, and you get lucky enough to start out in the middle of nowhere with no close neighbors, it rocks. If you wind up sandwiched between, say, Japan and the Aztecs, that lil' explorer guy doesn't do a heckuva lotta good.
EJ