Google's is adding "Caffeine" to it's search engine. I'm impressed. Here is a link to try it out: http://www2.sandbox.google.com/

In my opinion, It is faster as claimed. More importantly the search results are more accurate. Google search results were always weighted by the number of reciprocal links - how many sites linked to your site. This has been gamed over the years. My impression is that the new search algorithms gives reciprocal links less weight and content more weight. I'm impressed.