Raph Koster announced early last week that Metaplace, the online world that was supposed to be the end-all, do-all of such things, is going to close for good on January 1, 2010. It's a common story with MMO startups these days: developer has "revolutionary" idea for user-generated content, gets a bunch of money and support to put it into place, users don't actually vibe with the idea they way they were expected to, and the dev is left having to explain why it didn't work out.
Oh, and the people who were actually enjoying the world get stuck without a place to go. Koster says the company has created this Metaplace veterans forum for anyone who enjoyed the service and wants to stay in touch with their contacts there. We'd recommend you head over there to say hi (and talk about what's next), but given that the world is shutting down, odds are you probably weren't playing with it anyway.