Gamification is essentially a Points and Achievements system where you can earn Badges and possibly enhanced user access.
It's been done a million times at this point, and not successfully done within social media (for the most part) since it will force a user response and be manipulated. There is no "earning" in social media.
However, Treehouse does a really nice job of it with their courses, as well as with their community forums. In fact, they mention interesting ways to apply it within a few of their design and development workshops.
The only advice I would give you is to focus on enhancing a product with it, and not basing a product on it. That product should always dictate a rewards system - and, only if it's a valuable addition.