I don't have an iPod, but I plan to get one. For now, my phatbox will have to suffice in my VW.
Basically, what I'm going to be listening to on my iPod (when I get an E90) will be Dream Theater and not much else.
Okay, fine, some classical. Some Linkin Park. Some token fun-time stuff for dancing, etc. I'm sure I'll have a bunch of other stuff on there just in case the mood hits me, but it won't.