hi
I've been trying to create
something very similar , targeted solely to ebooks.
It's not as good and nice as Selfari or
Librarything (which the Selfari guys copied) but it's usable.
It's been built from off -the-shelf Drupal modules. I haven't had a chance to do much custom development on it.
I'd be open to working with anyone from the community to improve it.
regards
Sic.