Ya gots a point. I spent a solid week ripping all my albums onto my iPod without thinking what the bit rate was... turns out it was all done in 128. D'oh. There's no way I'm reripping all that again, so bands and albums I like more, or I think really need the higher quality, get the 256 treatment. The rest I'm just leaving as is.
Besides, everything wouldn't fit on it if it was all in higher bit rates... I've only 30G to work with here, people.