Planetbeing tweeted: Apple released 6.1.1 for the 4S only today. The JB still works fine. We will release an updated evasi0n that recognizes it as supported.
To be informed as soon as the update to Evasi0n is released please follow iClarified on Twitter, Facebook, Google+, or RSS.
You can find detailed instructions on how to jailbreak your specific device here.
Update: The jailbreak has been updated with 6.1.1 support!