Well, I've only had a T1 for a week. I'm coming off of a Kobo, where a tonne of books makes it difficult to navigate since it involved page after page of scrolling (or remembering keywords to search for). Even categories could only do so much.

Maybe Sony does it better. Then again, I rooted it and installed CoolReader within 2 days of buying it. (So I can use a directory structure to organize things, but I'd have to export something reasonable from calibre. Since I only have 93 books on my computer, it doesn't feel like it's worth the effort.)