We do something similiar to @jrockfl
Here is how we do things.
We run contests on FB, contests are usually the "vote" type meaning we accept photos posted to our wall and then the one with the most votes wins. We wrote the app ourselves, it really is quite straight forward to do so.
We have FB tied to twitter, so posts from FB go direct to there.
Not used pinterest much yet.
Was really quite interesting, we ran a contest to generate more likes, basically a "when we reach x likes we will give Z to charity". Somehow a large marketing company heard about it and did an article on us about how savvy our approach was and how quickly our likes rose.
The downpart of FB is that not all your fans see all your posts, you now have to pay to promote posts for higher visibility.