Happy Birthday Critical Mass
I think it's partially about bike-riders being able to share the roads with cars and also about reducing pollution. Both things I support in theory, though not in practice by riding a bike. One thing I don't like is that Critical Mass is not held to traffic laws. They get to ride through the streets, but don't have to stop at red lights.
To pedestrians such as myself, this sucks, as it causes people walking to have to wait over ten minutes to cross a street while hundreds of bike riders ignore red lights (with the police - on bikes themselves - looking on). Right now the city is working on creating traffic lanes that are designated for bikes. Maybe their next bike-related project will be encouraging bike-riders to adhere to traffic laws.
A girl can dream.