Darkangel is quite good. The sequels are good, too.
Funny, I liked Sundiver
a lot, but it stands a bit apart from the other "Uplift" books. It's really a mystery in an SF setting. The others are more space-opera, I think. (I liked them, too.)
I know what you mean about Earth
, I guess I just liked the exploration of online communities a lot (and the black hole stuff, too). And the idea of teens as "tribes."
I suppose I should also recommend The Diamond Age
in this context, though we've discussed it in this forum before.
@yvan, I should also recommend Iain Banks, particularly The Player of Games