I suspect there won't be support for any DRM book formats. This puts the device where non-Apple MP3 players are compared to the iPod -- an attractive, less expensive alternative to the "real thing", but you need to know a bit more about what you're doing to use one, and you also have to be able to take a certain kind of stand on fair use and copyright law.
I'd still get one for my 12 year old daughter if they were available, though.

(She actually
doesn't like my crumbly old yellow paperbacks that I've been saving for a generation for her!)