I can't quite agree that the book only supports fantasy, when 3 of the sample settings
aren't fantasy. (Sure, the sample backgrounds they give are the D&D races, but can you imagine how much they would've been asked how to build those if they hadn't included them?) There are plenty of skills and equipment to cover non-fantasy settings. (You skipped over the Computers skill, which would have been the only one I would have felt was missing.) Sure, they use the D&D categories for creatures, but they cover just about everything, and make conversions that much simpler.
As for those sample settings... I actually find Lux Aeternum to be most interesting. Normally I find space settings to be boring to play in. Something about this setting really grabbed me, though. Either that, or the lack of starship stats and endless sci-fi equipment just didn't put me to sleep.
I'm not terribly interested in the setting for Borrowed Time, but 9/10ths of the special feats for time manipulation they give felt custom made for a proper Matrix setting.
Overall, there are so
many d20 fantasy games, most of them with a pretty strong flavor, that True20 would probably be my
last choice for d20 fantasy... But it's my
first choice for d20 just-about-everything-else.