IMHO that's 2K Sports best chance at competing with EA in the NFL Exclusivity (screw the gamers) era.
2K Sports was on to something with APF2K8 but failed to take it far enough. The Team Builder here is another piece of the user generated content puzzle.
From a technology perspective we are in a highly customizable social networking age. Custom content rules, and sports companies should focus on tools, user generated content, and content publishing (game, website, community).