I used AirBnB for the first time on a recent trip in Istanbul. I only looked for hosts who had been previously positively reviewed and who were conveniently located. I pretty much had a whole floor to myself with my own private terrace that had great views of the Galata Tower, and I really enjoyed chatting with the host, her roommate, and some of her friends whom I met. I definitely see myself using the site again in the future.
I'm also on couchsurfing, but I have never actually couchsurfed before. If you have used both sites before, what are your thoughts of airbnb vs. couchsurfing?