I think that the demographics of gamers have been skewing older and older, and it's finally reached the point where a critical mass are past the age where they place significant value on the "newness" of a game.

You can still find 13-year-olds decrying PS3 and 360 games as being "unplayable" due to their perceived technological shortcomings, but every year they represent a smaller and smaller slice of the total market. The surveys I've seen lump 18-35 into one group, but I'd be interested to see the results of splitting that into two groups at around 26-27.