Recently I was digging around through Google's language tools to see if there was anything noteworthy -- and there I found several references to what they are calling Social Search. This feature was already a "Google Experiment" at the time -- but what these translations were hinting at was a more broad roll-out.
Google has announced that this new feature will begin showing up in your search results over the next couple days.
This feature basically gives more weight to results of things that appear in your social circle -- stuff that your friends have talked about. You're not going to see social results on every search you make, but when it does show up, you can be sure that it's going to contain information you will find interesting.
If you want to check out your "social circle", use this link. It can be a bit creepy seeing how much Google knows about your connections to people, but I guess that's life in 2010.