It is fair to say that the diffusion of Buffalo wings, while not over, is well under way. The photograph of wings is from Salsa Cabana, a Tex-Mex restaurant in Yotsuya, Japan. The treatment is somewhat traditional although the lettuce is unusual and the celery sticks are missing. In other words, the Buffalo wing region may have a diffusion center and a core but no periphery. In an attempt to identify a core, however, I have made use of the internet.
Buffalo is still the core of the region.
The Northeastern United States, particularly New York State and Pennsylvania, is still a region where you are more likely to find excellent Buffalo wings. The second map shows the locations of these restaurants in the region. So while this thirty-four year old food item that originated in the region is still strong in the Northeast, it has spread quite far. For its size, California seems to have few wings places people rave over. New England is mostly a wings desert and the Southwest, with its own spicy food customs, hardly shows up at all.