I agree with the overall point Harold. However, I do think that gameful design that incorporates collaboration can, at least in principle, contribute to social learning. To do so, however, it must enable social flow and focus on the social psychology rather than the psychology of why people play games. To my knowledge most approaches to gamification do not take this approach. The biggest reason games don't work at work, or at least not for long, is that a game, to be a game, must be voluntary. Otherwise, it can't evoke playfulness which is key to any game.

http://skilfulminds.com/2011/06/27/social-flow-and-collaboration-in-gameful-design/