Another vote for mountain. I've been running SPD-like cleats (Time ATACs to be exact) for over a decade and can unclip and get my foot down just as fast as as anyone riding platform pedals or toe-clips. Not that I need to often, being able to track-stand for a few seconds buys you some extra time.
There were some really good points made about traction, comfort, and being able to walk around in stores (or on ferries) without looking like a duck. I have the newer Shimano Look-style pedals on one of my bikes and though the shoes are super stiff and really comfortable when pedaling, I wouldn't even consider taking them on a tour.
Just picked up a pair of the Pearl Izumi clipless sneakers and really like them so far. When touring, I don't want to look like I'm part of the spandex mafia or that I'm out for a "workout" and I really liked the blend of casual styling with moderate stiffness in the sole.