The real news is that they have enabled download in the EPUB format in addition to pdf. This will be very handy source of reading material when you buy that Macbook Touch for Christmas. So the only stumbling block is that you cannot limit a book search to return only download-able (free) results.
Google just announced that it will now allow users to download over 1 million public domain books in the EPUB format. Google had already made this archive available to some of its partners, including Sony and Barnes and Noble, but until today users weren’t able to download these free EPUB texts from Google directly. Google will continue to make PDF versions of these books available for download as well, but users with eReader’s will find the new EPUB files far more useful.