We are adding RadTreeListView for ASP.NET Ajax in Q3 2010. Please see what is coming in ASP.NET track in this blog post
The RadTreeListView for Silverlight/WPF is available as an inheritor of GridViewDataControl since Q2 2010. It allows editing. Please check our online demos here
the Telerik team
Do you want to have your say when we set our development plans?
Do you want to know when a feature you care about is added or when a bug fixed?
Telerik Public Issue Tracking
system and vote to affect the priority of the items