Google's Caffeine is to help with indexing which helps speed up returns, and is supposed to be alot fasters. Here are some of the changes.
• The new Google Caffeine's search results URLs are different.
• Google Caffeine seems to improve Wikipedia results.
• Some .gov websites got lower rankings for core keywords.
• Google Caffeine seems to like good site structure and/or fast loading websites for top results.• Google Caffeine does not like duplicate content
My own take is that there are infastructure changes that are going to help google compete with some of the Bing technology!
www2.sandbox.google.com