Canon Powershot G2

It's not the packing of clothes I have a problem with, it's the music.
Tomorrow, I'll be on the train for about an hour and a half, which means I can probably listen to 2 or 3 cd's. So do I bring a dozen, so I have a choice? And if so, which 12 do I bring? Or should I take into account that I've been listening to the same Pinback cd almost all week, and figure that I'll just end up listening to that anyways?

This is almost harder than deciding which shoes to pack.