RequestFactory is good for any kind of bean-like-object. If you look at the DynaTableRf sample, the "backing store" is a trivial list of in-memory objects. There is a simplistic transaction model in the app to demonstrate JSR 303 validation.
The most important design aspect of RequestFactory is that it does "RPC by interface" instead of "by concrete type," so you don't have to worry about your server-side domain objects not being GWT-compatible or having to hand-roll DTOs. -- Bob Vawter Google Web Toolkit Team -- http://groups.google.com/group/Google-Web-Toolkit-Contributors
