Not really useful when so many geolocated images are so random. I don't necessarily want to see people's selfies or food pictures if I'm trying to see pics from a certain location.
Well, if I'm just wanting to check out photos, I want to see actual photos of the places. Not people taking selfies, close-up shots of food, or photos that are not relevant.
The value of spotsy, however, is that you get to see which local spots have the most instagram photos associated with it, which provides value in a different sort of way.
I can see the usefulness of the app in that regard, but not as a photo browsing app.