Realgm.com is reporting that Chris Andersen had surgery to repair a partial tear in his knee.
Personally I think this is good news because he was clearly hampered by it during the season. It says he should have a complete comeback by the first game of 2010-2011. Hopefully he can comeback from what was a disappointing year. The only downside I see is that he might get out of shape from being off the knee for so long, but only time can tell.