When we decided to add social features to our Chuck the Ball games, we were faced with the task of selecting a social gaming network. Our first choice was OpenFeint because it was free, had a lot of users, looked professional, and had an active developer community. OpenFeint also got bonus points for including the source code. We quickly ruled out the other major players due to cost, publisher-specific requirements, and lack of users and brand recognition.
Confident in our choice, we forged ahead with the integration. Fortunately for us, we were done forging after about 10 minutes! The initial integration was a snap and we had the basic functionality up and running in no time. Customizing the UI and changing a few of the behaviors of the client took a little work, but we easily found answers to all our questions in the forums.