Recently, I presented an ADO.NET Data Services session at TechDays in Montreal called "Goin' Up to the Data in the Sky: ADO.NET Data Services for Web Developers". At the end of my talk, I briefly showed a few resources links. Here they are:
Team blog
http://blogs.msdn.com/astoriateam/
Overview document
http://msdn.microsoft.com/en-us/library/cc956153.aspx
Using document
http://msdn.microsoft.com/en-us/library/cc907912.aspx
How to videos
http://msdn.microsoft.com/en-us/data/cc300162.aspx