Mike Flasko did an awesome talk on ADO.NET Data Services implementation that really covers everything in 1h:

- How to expose data, do server side paging, create friendly feeds, blob-streaming

- How to set security on ADO.NET Data Services

- How to set caching Client, Server Sides and Proxy Caching

- How to consume from SL4 with security and change tracking in EF and on client

- How to use Interceptors to restrict entity visibility and updates

- How to write an own Provider for ADO.NET Data Service (e.g. ADO.NET Data Service for Twitter Data)

AWESOME JOB!

I also recommend to checkout odata.org and the OData SDK ( Check out the OData SDK Sample Code to write own providers) and  learn more about the great client libraries and server libraries available for .NET / SL / JS / PHP / IPHONE…

Congratulations to the whole team and Pablo Castro for driving OData.