I'm working out the REST APIs that Adobe's new color theme app and social space, kuler (http://kuler.adobe.com) uses by watching network traffic between the Flash app and Adobe's servers. As has been discussed elsewhere, kuler uses REST apis (http requests) that return XML documents.
You can try it out by logging in below, then clicking "Get Themes" to view your themes pulled from kuler's API. Note: the password is sent in the clear, as that's how the kuler Flash application does it.
Then view the documentation, and discuss on the blog post.
Login
Log into kuler to get the userid.
Search
Search Themes.