The ADO.NET Team blog mentions that the ADO.NET Entity Framework and ADO.NET Data Services will be shipping with Visual Studio 2008 Service Pack 1 and .NET 3.5 Framework Service Pack 1. We don't have a date for the service packs, but apparently we will get a peek before then in the Service Pack 1 Beta. Read more here.
In the meantime, check out the Free Training for Entity Framework and ADO.NET Data Services.
Here are some recent MIX 08 Videos for ADO.NET Data Services: