In the new infrastructure so far I think there is... *an increased weighting on domain authority & some authoritative tag type pages ranking (like Technorati tag pages + Facebook tag pages), as well as pages on sites like Scribd ranking for some long tail queries based mostly on domain authority and sorta spammy on page text *perhaps slightly more weight on exact match domain names *perhaps a bit better understanding of related words / synonyms *tuning down some of the exposure for video & some universal search results Source:seobook.com/google-caffeine
I think nobody knows exactly what it is. I hope very soon we will see the new project. I hope we won't be very shocked by it.