I've been playing with the site this morning, and I cannot seem to find any restrictions on the files you upload . There does not seem to be any of the sharing types of DRM found on the Kindle and Nook platforms, and while there are no copyrighted ebooks on the site right now, I do not see any restrictions which would stop me from adding them.
The content currently on the site are all public domain titles, and they arranged by topic and thematic bookshelves. Users have the option of uploading their own ebooks and organizing their own shelves. They can also browse shelves created by other users, and if they find a title they like it can be added to a personal collection for later download.
If that sounds suspiciously similar to file sharing and/or piracy, you're not far off. I won't claim that this site is designed to encourage piracy, and it seems Rick truly does not intend for that to happen. "I don't want people to pirate material. I want people to buy books and respect authors," Rick said.
But I can easily see a publisher might feel that way. And other than Ownshelf's TOC, there seems to be little to prevent piracy.
Going forward, Rick plans to continue to polish the site and let it grow organically. I'm told he also wants to partner with publishers and self-published authors so they can use the site to share their own ebooks.