One thing I dislike about my current music collection is that it is fragmented across a number of devices, and I have lots of songs labeled like: track 08. I don't really feel like I have a collection anymore. I suppose I could spend a day making sense of it, but I doubt that I will.
My anal retentiveness even permeates my digital music collection. I have a very tidy music folder and have recently started adding the year and label of each album I have. I'm always amazed when I use other people's ipods to see how disheveled they are. I think, for me, it comes down to how strongly I feel about the album as a complete expression of an artist or band's vision. My albums have to be intact to be able to complete the journey and having a track out of place would be like ripping out chapters in a book and pressing shuffle.
for me my last.fm charts has somehow taken the place on my physical collection.