The always insightful Stuart Dredge over at MobileEntertainment has crunched some numbers on Game Center's actual popularity. Since Apple's own gaming social network on the iPhone launched, I've heard lots of different things from developers in terms of how they're implementing and using it. Some developers jumped in head-first, bringing all of their apps on board quickly, while others have only brought one or two apps on board at a time, waiting and seeing what their users are into. And some developers haven't even started on it yet, instead waiting to see how adoption works.
So in order to get something resembling hard numbers, Dredge took the reported sales of a few popular App Store apps, and compared those to the num
