Tripzie (Ive Been)!
The social competition against your friends to see who can visit more included locations. Were adding new locations constantly. Some will be there for months, others just briefly. When you are near a location visit it, check-in to claim the Tripzie. Why not take a selfie and submit it to Facebook & Twitter?
You can score against your friends by searching for them and following them and getting them to follow you. Your leaderboard then shows how you are doing against your friends.
If you prefer not to sign in with Facebook then you can still see what Tripzie is about, but you will need to sign in to be able to record your own Tripzies and to connect with other users.