I don't go crazy about sound quality but I do generally pick higher quality bitrates then most people when converting cd's over. Afterall you have what, 32 gigs or so on most models? Go for a lil more quality over those people who just fill it up with a ton of music with horrible quality and wont listen to half of them. I would consider doing lossless formats if more players would support them better.
Another big factor is everyone uses crap for headphones/speakers, so the quality of the compression doesn't matter since the headphone will introduce bad sound anyways. I do have some very spiffy headphones

I generally am listening to music almost all day. I have both a pandora and napster subscription. Pandora for when I'm feeling like finding a new artist or just having random music I don't have to pick since its pretty good at finding stuff. Sure it has some horrible picks, and it seems to have thumbs upped a TON of songs I know ive never listened to or would NEVER thumb up.. but whatever. Maybe I left it open somewhere and someone else did... /shrug. Napster is more for when I'm wanting to pick and choose a playlist, and I also use it to get 5 songs/month.
But at work I can listen to music, at home I do, when on campus between classes, etc.