We have some guidance from Scott Guthrie, General Manager with Microsoft Developer Division about the roadmap of "Atlas".

ISVs that are actively using or planning to use Atlas to create rich Ajax web application would benefit learning more about the roadmap and naming for "Atlas" from Scott's blog -

http://weblogs.asp.net/scottgu/archive/2006/09/11/_2200_Atlas_2200_-1.0-Naming-and-Roadmap.aspx