RIA Services support for AJAX
This would be very useful for companies wich want to port their Silverlight apps to HTML 5
This item is for much more than what you can do with JSON endpoint today. The idea is to provide a compelling client for Ajax that covers identity, query support, change tracking, rich databinding etc.
Paulo Aboim Pinto commented
there are support for RIA Services for Windows Phone 7, WPF or AJAX. Check here: http://channel9.msdn.com/shows/SilverlightTV/Silverlight-TV-26-Exposing-SOAP-OData-and-JSON-Endpoints-for-RIA-Services/