Havent tried the Co-op yet, been playing mostly Cops and Crooks.
The cops start in cars,with mp5's (i think) and know exacly where the crooks are at all times.
the crooks start on foot, with pistols, and they need to head to an exit point to win.
its allot of fun, but, the way the multiplayer match making is set up.. you spend 15 minuts to get into a 5 minut game, it sucks