I don't have solid data, just my own year-to-year experience, but it feels like gaming cosplay has been on the rise since we first started attending Sakuracon. The Team Fortress 2 crews you've seen showcased on the gaming blogs are one of the newer ones, but Valve seemed to rule the crossover space this year: there were several Chells as well, as well as Aperture Science Technicians, their Weighted Companion Cubes in tow. These cubes were sometimes literally in tow, hoisted up on crates for easy transport. There was even a GlaDOS.
