i really don't think in 'genres' , but here's some of my favourites anyway:
i tend to stay away fom radio friendly music (well, i like coldplay... they're radio friendly) so pretty much everything that's not easily accessable ... i like a challange....
western art music (esp romantic . 20thC music, english, russian, french composers...)
electronic dance music (esp deep house, dnb, breaks... probably other stuff too , but not vocal house or anything with too much vocals in it - i think it defeats the purpose of dance music
crap / junk / punk rock
any experimental stuff
any 'art' or 'anti art' music...
a new interest for me is "outsider music": eg the shaggs, jandek... very interesting stuff.
artists of note:
radio head the mars volta, muse, pedro the lion (although "
control" was very depressing, i could only listen to it twice... then i had to listen to some news boys as a pickmeup
) the blamed, sf59 (of course) joy electric, debussy, dvorak, edward elgar... bands you've probably not heard of like hdu, wendyhouse, darcy clay, the clean, the chills, the double happies, the verlains .. blah blajh blahys
i could go on and on and on...
but i'll end it there