That was the point of the study. To see if modern games could be used as effective soldier trainer tools. When I say "they found this and that" I mean they took some soldier and some FPS gamers, gave'em guns and said "shoot that target over there". The solider performed as expected, the FPS gamers performed far above and beyond what was expected. To say that we have a bunch of video game programmed sleeper agents or something walking among the population is an exaggeration, of course, but we at least know that the practical knowledge aspect of the job (the other parts being experience and physical training) can be satisfied with a PS3.
Edit: Note that I'm not trying to make any claims here. Just reiterating an interesting study I read. I doubt anything will really come of most of it, aside from refining solider training programs.