Today Google announced it is launching a new upgraded version of its search engine. It even went as far as releasing the developers preview of it today, code named "Caffeine". In the announcement they explain that it will improve the speed, accuracy, size, and comprehensiveness of Google search.
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Also, it looks like Facebook are getting serious about search. In particular the FriendFeed acquisition looks very exciting. Learn more here and here. The race for a private and public real time aggregated semantic capable search market has got a lot more interesting. This union is a very significant move that could be Twitter's biggest challenge yet. And it is the joining of the very talented industry recognised founders of the FriendFeed engineering team who were instrumental in launching Google Mail and Google Maps at their time in Google that could be the biggest cout of all.