Dave asks, "Metaverse, anyone?", and I say, Raph Koster is trying to get you to say, "Metaplace." He too is moving out of the thick-client virtual world arena, and into the social-network-qua-MMO space.
Right now, it's a chatroom with aspirations. The fuzzy future conception of apps like this is that they're a no- or minimal-client (aside from the web browser) virtual world that leverages the capabilities and strengths of social networks. The thing is, I think there's a fundamental tension in the game part and the social part.
In MMOs, folks really focused on the goals of the game are often the least social members. The most social folks get less from the game, and more from the 3D chatroom that the game is for them. How you get one aspect to benefit from the other is, I think, a lot trickier than folks assume.
The Sims Online was a very close attempt at this fusion, and it failed horribly (and it was using the biggest selling game of all time as its springboard). I don't know that it failed because of its design, as much as it failed by trying to wed game goals with a mostly social experience. Competition carries a strong anti-social component, part of that lizard-brain instruction set that says, "Beat the other guy." When there is serious game involved, in a progression, perpetual sense, a lot of the folks that cling to a social network will fall away, not wanting to get so involved in something like that, and you'll be left with MMO players.
At least, that's what I pessimistically think. I've been wrong before.
