The driving part certainly looked like more fun and excitement than mowing down waves of dudes in another corridor, but I'm confident there will still be plenty of that.
You call the marketplace, a large open space with lots of scalable buildings and guys at every angle, with almost every surface destructible, a crazy APC chasing you, with being grabbed by a guy and beaten up before Sully dynamically intervenes, with scaling buildings on-the-fly to escape a choke point, and punching a dude with a giant drop-strike...
'Mowing down waves of dudes in another corridor'?
What large open space? All the combat occurred in a narrow, linear area. "Straight down this street 30-foot-wide, up these stairs, through this door." And a corridor is still a corridor, even if you can climb on top of some of the furniture (which I also remember doing in previous Uncharted games).
I know I'm in the minority here, but I think the combat in Uncharted games is just a boring obstruction to get through for the fun parts.