One service, reCaptcha, has sought to not only help people cut down on bots but also improve OCR (optical character recognition) software. The free service has become quite popular since its inception, and ended up being quite attractive to some, namely Google.
The search-giant has acquired reCaptcha for
Some have claimed that reCaptcha is a self-defeating service. If you teach computers to read more effectively, CAPTCHA technology, by its very nature, becomes less useful -- which may lead one to conclude that Google's aim isn't to improve anti-bot technologies.
Instead, Google may put it to use in their own OCR endeavors. It's very likely that Google wants to capitalize on reCaptcha to improve their book scanning project. Still, in the short term that will serve only to help reCaptcha, since they will probably receive a considerable cash infusion to spurn development.