Oh boy. According to a Gamasutra report, several members of the Crackdown development team - including lead designer Billy Thomson - have formed a new development studio. And "may" be working on Crackdown 2.
The "form a new studio" bit, that's legit. They're called Ruffian Games, and are based in Dundee, Scotland. But the Crackdown bit?
Gamasutra only state that there are "unconfirmed reports" that the studio are working on it at the moment. Though it's certainly possible, what with the composition of this team, the fact they're not at Realtime (who developed Crackdown) working on APB and the fact Microsoft got awful coy the other day about the possibility of a second Crackdown.