I've been living and working in Ho Chi Minh City, Vietnam for a year and a few months. This has been the year when after having had a motorbike learners permit in my home in Australia but never having followed thorough with it, I finally got around to getting a motorcycle license.
Vietnam is a wonderful country to ride a motorcycle. Most of the traffic on the roads are motorbikes. On smaller rural roads almost all of the traffic is 2-wheel.
Motorbikes are an integral part of the Vietnamese economy. The per-capita GDP of Vietnam is still under US$800pa (rising to about $2000pa in the HCMC region) so people just can't afford cars. But more than that, Vietnamese like riding motorbikes. If you see Viet Kieu (returned Vietnemese from places like the US) who come back to Vietnam, they don't buy a flash car - they buy a flash motorbike.
Bikes are used to transport everyone and everything. From market goods to building materials, they all go on the back of bikes.
These are photos from the Streets of Vietnam.