Elfy-Welfies, War Bores, Decadent Vamps and Licensed Crap. Interesting read - very true too. Sturgeon's Law is, unfortunately, out of date now - far more than 90% of science fiction is crud these days.

I have to say, I think that there are other sub-genres - Hard Sci Fi (I'm a big Greg Egan fan) is one. Then you have cyberpunk, Space Opera and whatever the genre Richard Morgan, Alastair Reynolds and Neal Asher are working in is called. Sci Fi Noir, perhaps? Anyway, I digress - and loads more that I can't be bothered to enumerate.