And not just in terms of games you play on the phone. He does say that casual phone games will become more social, but he also says that huge MMOs like World of Warcraft will attempt to develop casual, mobile versions that can be "played" from a phone, and have an effect in the game itself. As in, you'll play a quick casual game on your phone, and how you do on that game will give you XP or skill points or even some extra cash in the online game.
I doubt Blizzard will be the first to jump on such a bandwagon-- their history is releasing polished games on established platforms, not breaking new ground. But it's easy to see how a smaller, up-and-coming, very API friendly game might try to duck into the mobile software space, and put together a model for how MMObile or MMO-to-go games might work.