Microsoft decided to join the Open Content Alliance (OCA) lead by Yahoo! and other partners. This is yet another area in which Microsoft will be working on, with Yahoo! (the other being the recently announced IM integration). I think more and more big players (of whatever are left out there) will come to the logical conclusion of joining the OCA rather than going alone with any book scanning project. It just seems to make more “sense”.
It would be interesting to watch you wins this race. It seems obvious that most search engines will be be including results as part of daily searches. Given this fact Google seems to be the obvious answer, since it generates the maximum number of searches online. But given that Yahoo! and MSN search have been ramping up their operations and doing pretty good at it, its a little to early to announce any future winners!