The guys at Intersoft Solutions are working hard on some interesting products for creating business applications in Silverlight 2. Among them are datasource controls for Silverlight 2, something that is sorely lacking in the Microsoft release.
If you've found retrieving and binding to data a royal pita, you'll be interested in the XmlDataSource, WcfDataSource, and AstoriaDataSource controls they're planning to release this year.
Here's a bit about the ADO.NET Data Services support:
"When using AstoriaDataSource as the datasource control, our upcoming Silverlight databound controls will perform data operations automatically, such as data selecting, data paging, data transactions (Insert, Update, Delete) as well as data manipulations (sorting, filtering)."