Lights are definitely a good idea. Oh, forget to mention that Critical Mass gets a good turnout here, if that's your cup of tea. In the warmer months, the rides are amazingly huge and fun.

Anyway, bike-friendly is all relative. I visited a friend in Philadelphia two months ago and rode her hybrid around. That place seems a lot better for city cycling than Seattle even though it's more congested. Cyclists were everywhere, and bike lanes seemed better weaved into the fabric of the city.