Raph highlighted some of the recent posts that have been made to the Metaplace website. For the non-technical, you'll want to check out their business plan or the interview I did with him right after the initial announcement. Artists will be interested to learn what the framework's art integration process is like. Those of us who can only draw stick people can also enjoy the perty pictures. And, if you are technical, you can take a gander at the description of the Metaplace event system - the guts of how gamer input is handled by the framework.
Think all of that sounds fascinating? They're hiring! They're looking for an experienced Flash Programmer, a Software/Client Engineer, and a LAMP Dev.
For an overview of the whole situation with Metaplace as it stands, Next Generation has up an interview with Raph nailing down the particulars of the project in layman's terms: We have a motto: build anything and play anything from anywhere. But Metaplace isn't built solely around massively multiplayer games. You can make single player games as well. We've already made things like puzzle games, 2D overhead space combat games, and we're working on RPGs and MMORPGs, so really it means any of those things. I don't doubt that there'll be things that the platform can't make, but we'll figure out ways so it will.