Well I have been using this little bit of geo location based social media for about one month now. So far I LIKE IT, its fun and I enjoy unlocking the content. Its good as you can see where and what your friends are up to (if they have it of course).
I have mainly been using it on my iPhone as it has the geo tagging enabled. It links very nicely into apps like TWEETIE 2 and the iPhone facebook app.
If you have not tried Foursquare I would definitely recommend it.
