Ahh... You're right. It is being devoloped by Leeds and North. They don't have either of the devoloper's sights listed on the official sight of Chinatown Wars so i wasn't sure. Still it's had to be in development for a while tho... Rockstar doesn't usually announce their games until they have some stuff to back it up. Least that's what I think.
props to Ænemy for the sig