Should the Giants and Buster Posey be talking extension yet?

He's only 25, but Buster Posey has accomplished a great deal in his MLB career. His list of achievements includes being named the NL Rookie of the Year in 2010, winning an MVP award in 2012, and a couple of World Series titles with the San Francisco Giants. Not bad. The fact that Posey has accomplished so much in such a short time has already ignited some talk about a potential extension for the Giants' backstop. Given what we've seen from him so far, that type of talk could obviously be warranted. But is it too soon to start talking extension? With their roster almost virtually set for the 2013 season, that is the debate that fans and writers, both inside and out of San Francisco, find themselves in. Do the Giants get an early jump on it and sign Posey to an extension, or wait until it gets closer to free agency before throwing big money at their star catcher? It's important to note that Posey is not a free agent until 2017. He's under team control...