We've just posted a one-pager on transparent caching support in Entity Framework on our EFDesign blog.

http://blogs.msdn.com/efdesign/archive/2008/07/09/transparent-caching-support-in-the-entity-framework.aspx

We want to make sure that you will be able to interface EF caching with various caching solutions, so we would be very grateful for comments on proposed ICache interface.