This is only slightly related, but the PS3 has experienced "Year-on-year" sales growth, and it's been about a year since Kevin Butler was introduced in an MLB 09: The Show commercial.
While I'm not saying correlation yields causation, I would venture to say that we'll be seeing Kevin Butler for some time now, since a lot of the more vocal fans seem to love him, the commercials seem cheap to produce, as they lack fantastical special effects, and they do get the point across: The PS3 has games people want to play. It's leagues better than a lot of what was there before.
That said, I don't think he should be used to market Move, at least not this initial batch of Move games, at all. It's a mis-match. I've looked at several of them, just for the sake of my podcast, and they don't line up with the desires of "core" gamers, the folks who seem to love Kevin Butler so much. I'd bring him in once they release the Ratchet and Clank multiplayer title, have Socom 4 move controls patched in, or bring out the Resident Evil 5 patch, instead. Seems like that might be a better fit for him than, say, Tumble or Sports Champions.