Well, my post isn't going to help you much, as I can't address your needs for 20-60GB, video, or even pictures...
That said, here's a link to the successor to the compact mp3 player that I settled on a little over a year ago:
http://store.yahoo.com/frontierstore/nex4gbhitoem.html
I bought my Nex1a for the following reasons:
*AA batteries- I can charge my own cheap batteries.
*CF memory- size available is dependent on what you put in!
*it came shipped (then) with a 1GB microdrive for less than the cost of said microdrive.
*acts like a memory stick.

The NexBlack (linked) will come with the 4GB Hitachi microdrive for about what I paid a while ago... typical tech story. Reading about the NexBlack makes me want to upgrade... but I so rarely use my mp3 player it's just not worth it. Airplane flights is about it, otherwise, the white noise of the everyday is my chosen companion when I'm out and about.

Anyway, folders are not a problem, though, so that's about the only 'on-topic' comment I can make!