So iTunes 9 has a new feature called Genius mixes, where it pulls music from your library and creates mixes by genre. Post what you've got to give us a good idea of what your music library's like, screenshot if you'd like to.
I'm missing a bit of music but this is pretty accurate to what I listen to on a daily basis.
Alternative Mix, based on Coldplay, Travis, Radiohead
Alternative Mix 2, based on Grizzly Bear, Rilo Kiley, Death Cab for Cutie
Indie Mix, based on The Shins, The Killers, Broken Social Scene
Alternative Rock Mix, based on Metric, Franz Ferdinand, Arcade Fire
Indie Mix 2, based on Ingrid Michaelson, Sufjan Stevens, Glen Hansard & Market Irglova
Alternative Mix, based on Red Hot Chili Peppers, White Stripes, Maximo Park
Alternative Mix, based on Fleet Foxes, Belle and Sebastian, She & Him
Indie Mix 3, based on Ted Leo and the Pharmacists, James Morrison, The Dodos
Alternative Mix, based on Neko Case, Bon Iver, Various Artists
Soundtrack Mix, based on Jonny Greenwood, Dario Marianelli, Mateo Messina
Indie Mix 4, based on Thom Yorke, TV on the Radio, Dirty Projectors
R&B Mix, based on Robin Thicke, N.E.R.D., Justin Timberlake