The official source of information on Managed Providers, DataSet & Entity Framework from Microsoft
The information in this post is out of date.
Visit msdn.com/data/ef for the latest information on current and past releases of EF.
We recently posted a whitepaper (written by Scott Allen) on MSDN that demonstrates ways to write testable code with EF4. You can read the article here, and if you have feedback please post it in the comments below.