I highly recommend checking out Astoria.  Pablo Castro, a major driving force behind Astoria, was on Dot Net Rocks recently, and the show provides a great introduction to Astoria.  Of course, you might also want to take a look at the Astoria Team Blog.

Essentially Astoria (aka ADO.Net Data Services) provides a REST-oriented web-service over data sources which is URI based and has a limited set of standardized operations over the data.  It works really well with the Entity Framework and can provide a simple and very effective way to expose EF (or other) data to AJAX clients or any consumer of a web-data service.  Very cool!

 - Danny