One of my favorite things to do in new cities is to observe how the traffic works. Traffic in each place has a different feel to it that depends on the culture, physical space, population density, legal situation, and modes of transportation available (and unavailable).
Everyone drives in LA and Minneapolis, even if you’re only going a few blocks. In San francisco, pedestrians rule the streets…if a pedestrian steps out into the crosswalk, traffic immediately stops and will stay stopped as long as people are crossing, even if that means the cars are going nowhere, which is great if you’re walking and maddening if you’re driving. In many cities, both in the US and Europe, people will not cross in a crosswalk against the light and will never jaywalk. In many European cities, city streets are narrow and filled with pedestrians, slowing car traffic. US cities are starting to build bike lanes on their streets, following the example of some European cities.
In NYC, cars and pedestrians take turns, depending on who has the right-of-way and the opportunity, with the latter often trumping the former. Cabs comprise much of the traffic and lanes are often a suggestion rather than a rule, more than in other US cities. With few designated bike lanes, cycling can be dangerous in the fast, heavy traffic of Manhattan. So too can cyclers be dangerous; bike messengers will speed right through busy crosswalks with nothing but a whistle to warn you.
In Bangkok, traffic is aggressive, hostile even. If a driver needs a space, he just moves over, no matter if another car is there or not. Being a pedestrian is a dangerous proposition here; traffic will often not stop if you step out into a crosswalk and it’s impossible to cross in some places without the aid of a stoplight or overpass (both of which are rare). More than any other place I’ve been, I didn’t like how the traffic worked in Bangkok, either on foot or in a car.
Traffic in Saigon reminds me a bit of that in Beijing when I visited there in 1996. Lots of communication goes on in traffic here and it makes it flow fairly well. Cars honk to let people know they’re coming over, to warn people they shouldn’t pull in, motorbikes honk when they need to cross traffic, and cars & motorbikes honk at pedestrians when it’s unsafe for them to cross. Traffic moves slow to accommodate cars, the legions of motorbikes (the primary mode of transportation here), and pedestrians all at the same time. Crossing the street involves stepping out, walking slowly, and letting the traffic flow around you. Drivers merging into traffic often don’t even look before pulling out; they know the traffic will flow around them. The system requires a lot of trust, but the slow speed and amount of communication make it manageable.
 This is the principle behind traffic calming.
 That traffic calming business again.
 Not that it’s not scary as hell too. American pedestrians are taught to fear cars (don’t play in the street, look both ways before crossing the street, watch out for drunk drivers) and trusting them to avoid you while you’re basically the frog in Frogger…well, it takes a little getting used to.