The Indigo & Avalon CTP (Community Technology Preview) is available for download here:

http://www.microsoft.com/downloads/details.aspx?familyid=85AB132B-F1AA-4422-B053-272D79863013&displaylang=en

Maybe this announcement has a chance to be lost across all sorts of new stuff coming from Microsoft lately. But, believe me, these two technologies are going to change the way we are doing GUI & distributed programming for the next ten years. A new era is starting right now...