The personalized search wars are beginning in earnest.

Google started mixing in content shared on Buzz into social search today. For people with friends who are avid users of Buzz, the move should fill out their personalized search results, which have been pretty spartan for the last half-year. Social search has had little more than Google Blogger, Picasa and Reader to grab content from.

First unveiled last fall, social search augments Google results with links shared or published by friends. For example, if your friend shared an interesting link about the financial crisis in Europe, that might show up the next time you search for information on the economic fallout in the region. Or if you’re looking for the best fried rice recipe, ones from your friends might appear at the bottom of the page. Only publicly shared content will show up in results.

Content comes from your “social circle,” or friends you’ve made through a Google profile, people you Gchat with often or people you’ve followed on Reader or Buzz. More importantly, if a user has linked their account with another service like Twitter, Google will siphon in contacts followed on the microblogging service. Google needs to expand the number of relationships it’s explicitly allowed to track in order to catch up with Facebook, where the average user has 130 friends.

The boost comes at a sensitive time for Google. It’s clear that personalized search, which Google has been dabbling with for at least three years, is the future. An interesting question is whether Google, the undisputed king of search, can be the better provider of that experience five years down the line, or whether another company — namely Facebook — will.