It may not be for Durango, it might be for the 360, but I think it's unlikely at this point. Sony? Even less likely. They teased the game with a pic showing a part of PGR's London track, they're working on a game they can't name yet (so probably a known property) for a big publisher, they're made out of a bunch of ex-Bizarre people, and we know Microsoft has been actively looking for a new team to take over the PGR franchise (which they fully own). So either Lucid are being rather cheeky trolls or they're working on the next PGR, possibly together with another studio (and Playground would indeed be a great choice, considering how they're pretty big, have some experience as a team, and also employ a number of ex-Bizarre folks).