This is somewhat of a branch off of Google's Book Search project, at least the Google Books Help forum, where is the place people went for Book Search support, is also housing support for the new eBook support team.
Google says this opens up reading books digitally, since the books are in the cloud, you should be able to use any device to read your books. From desktop computer, tablet PC, to mobile phone device - the "choice" is yours.
Here is the Google Video demo:
Chris Sherman has his review at Search Engine Land.