Interesting! I know you are not the only one asking more than hundred questions regarding various areas nationwide since four years ago. The good thing is since four years ago, SR has not changed its social scene yet. GGB toll is only $6. Come here to take a quick look. That is better than any answer here.
I have lived in San Rafael for 11 years now. I grew up in Mill Valley and have also lived in Fairfax and Novato. San Rafael in my opinion combines a city feel, diversity of cultures, business services, and eating and night life that most of the other cities in Marin don't offer. It also has a little something for everyone, from the young and hip to the older more established, all at an affordable price. People are friendly, communicative, and go out of there way to connect with others. San Rafael is a centrally located, vibrant community that has a lot to offer.