And it's a wonderful way to get around both city and country. Motorbikes reduce overall traffic, can fit about 8-10 vehicles into a car parking footprint, have generally low fuel emissions (and can be even lower — lots of new small bikes get ~80 mpg in real world use), and never have trouble finding parking.
Speaking for myself, it makes commuting from the East Bay into San Francisco, not just tolerable, but something to look forward to. 21-25 minutes door to door at peak rush hour; park for free; the view from the bridge is superb.
Of course, the danger of cruising through a flood of slow-moving, angry, distracted, stop-and-go car traffic is considerable — but there's good reason to think (CA CHP motorcycle cop accident statistics) that it doesn't have to be much more dangerous than driving in the first place.