Last night Jeff Teper announced a SP2 issue where a product expiration date was improperly set. After installation the licensing may be set to Evaluation which will cause the farm to stop working after 180 days. MS is working on a hotfix, but in the mean time your farms are fine. Even if you fail to install the forthcoming hotfix your farm will not be accessible to users but your data is safe and secure until the patch is applied.
Soon there will be a KB article (971620) that will explain a manual fix. Expect the KB article in the next day or two.