GetGlue, the lastest Foursquare-style check-in site has recently launched a Blackberry app. Although this application is currently in Private Beta, they seem to be accepting tons of testers, as I recieved a download link within 24 hours of signing up. If you don't get an invite, you can always use their mobile site instead.
You're still wondering what is GetGlue? Well, it enables users to check-in to TV shows, movies, music and books, plus let's them see what their friends are watching/listening/reading in real-time.