Simon Brown has a nice DXTC library, and some other good stuff on his page; good page on spherical harmonics for example.
Shawn Hargreaves has a good blog that's mainly on introduction-to-game-development kind of stuff, mostly with XNA. I don't know how many commercial people are actually using the whole XNA studio thing, but I guess I might have to make Oodle work with their "Content Pipeline" thing.
Wolfgang Engel's blog is pretty good. Apparently he made an iPhone game SDK.