Double Fine head Tim Schafer told Gamasutra, "It's true the publishing rights have reverted to Double Fine, but there are some more deals that need to be worked out and contracts that need signing before that actually means anything, financially."
Schafer said that once that's all squared away the studio will have something fun to announce ... but "it's not Psychonauts 2." Double Fine has always retained the IP rights to Psychonauts, and Schafer has stated previously that a sequel is dependent on a publisher paying the way.
Update: Tim Schafer's comment to Joystiq can be found after the break.
Double Fine has always owned the intellectual property rights to the Psychonauts franchise. So we have always been free to pursue movies, sequels, etc.
What's changed recently is that the publishing rights to the game Psychonauts have reverted to Double Fine. Some deals still need to be finalized before this means anything financially. When that happens, we'll have more to announce.