I grew up in the Northwest; Olympia for my childhood, then lived in Seattle for 12+ years. I moved to SF in the mid 80's and frankly, I think the SF area has it all. I now live in Marin, and commute daily across the GG Bridge to SF. There is a great combination of on and off road riding right out my back door. The weather is predictable and rain minimal. I usually lose less than 20 commute days per year due to weather (and I am by no means hardcore about riding in the rain). I can almost always count on good riding on the weekend. From my experience cars are not an issue generally, and I am treated respectfully on the road. One downside I would see is less rideable single track. The hikers/horsers have managed to be better organized, and gotten bikes off most of the singletrack in Marin. You travel further north, or down to Santa Cruz for more singletrack if you like.

Cost is another issue. While I know the NW has gone up in price much in the past 20 years, the Bay is still a tough nut to crack financially. There is also a lot of money around here, and you need to not get caught up trying to keep up. I see lots of folks get caught up- gotta have a better car, bike, house etc. and before they know it they have more debt than fun.

I find plenty to do in terms of nightlife. Both from the club scene, and other things liek art, live acting, symphony etc. Its all here. Lots of folks pu-pu the music scene. But like any area you need to know the spots, and know the music you like. Its there, you just need to look. Crime in Marin is low. Crime in SF is as it is in any big city- bad in some spots, less bad in others. THe homeless situation in SF is sobering, more so than Seattle.

Seattle is great, and I am in no way knocking it. My folks and many friends still live there, and I love to visit. But for my experience having spent about half my life in each place, I choose SF. Your mileage may vary......