The Dev Team has distributed jailbreaks for all the previous iPhones (and basically all the iPod touches, and the iPad 1, and one Dev Team member published a jailbreak for the iPad 2 on one version of iOS).

That said, MuscleNerd states very clearly in his tweets that this 4S jailbreak is a work in progress ("Huge missing pieces prevent public release. LOTS of work left") with no promised release dates.