I did the San Francisco roommate thing for six months. It was a mixed bag and I have stories, pretty much all you can ask for. It's a great city! It's also broken and overpriced, so I live down the peninsula now. It's a little slower but nice to have my own place. You do what you have to do.
I would absolutely love it if a pretty girl would give me a reason to never have to log onto OK Cupid again. But more than that, would be up for a coffee with someone who wants to talk about how scary the world seems sometimes.