I used Gowalla, and I have to say that miss it. I know that Foursquare "won" or whatever but it really has never matched the fun I had on Gowalla. Why?
Foursquare, especially in the latest versions is extremely well designed. I like it for discovery, for a chance meeting up with friends, and for finding something near by to go to now sometimes in much the same way I use yelp. But I've never cared about the game. I dont care about the points, the mayorships, etc. I think most people dont, otherwise there wouldnt be a need for real world rewards for mayorships.
I do like the idea of location based games.
I like the idea of tracking my travels and giving myself something fun to play with friends that involves the real world. Gowalla had less emphasis on checking in and more on a collection game. In Gowalla you collected items. Some of them were rare, some abundant. Growing your collection involved, in many cases, trading with friends and an element of luck in what you would receive when checking in.
Turf Geography Club has brought some of th fun back to a location based game. There is some luck invovled in taking over a building. An element of defense by adding levels to your build and making it more costly to take over. And a good game play between friends as we fight over ownership of commonly visited properties.
Keeping it interesting.
That's still going to be a challenge. It's need a critial mass of friends playing to keep it interesting. It will also face a time when I'm just tried of checking in, not geting enough of a return in value for my time in the app. Hopefully, the game continues to evolve to keep it interesting. But so far I like it. So if your ready to try to steal my turf, go download it.