I just got back from a night ride. Went longer today as I work from home on a Friday and can set-off at 4pm sharp. I wanted to test out a new MagicShine light I picked up from dealextreme.com:
They claim that its as bright as a car headlight. I can confirm - it is! Super bright, and as I like to ride after work days it should get lots of use. Highly recommended. Took forever to get here (4 weeks) but worth the wait. Lights up a good area with a nice spread. These dark nights were a hazard with my old Planet Bike Blaze 2w.
The big difference was lighting up the shadows on a descent. I had been keeping it to 10-11mph as I simply could not see with the PB. The MS throws out a lot of light where I had no issue "letting it go" on a descent. Highly Recommended!