I also was just doing some research and read a couple of different things that say the Nook allows you to use the ebooks from the library. Overall the jist I have seen is that the Kindle only accepts material that is formatted by Kindle/Amazon. This seems to be an issue with some people and not so much with others. I have seen where people say that they are able to reformat material so that it is usable by the Kindle even though it is not technically supposed to be. I don't know how easy or hard that would be. Honestly I don't know if I would ever even use the share or library function but it makes me feel just little bit better knowing that I could if I wanted to. It also makes me feel like Barnes & Noble is considering its customers and not just its bottom line.