Looking at the official Silverlight 2 documentation, no, the model is the same as WPF. It's vastly simplified (Dispatcher doesn't have the concept of priority, for instance), but still the same model. Actually, I find it interesting that Dispatcher doesn't
have an Invoke method. For that matter, DispatcherOperation doesn't have a Wait() method. This means Silverlight provides "one way" context switches, and you have to roll your own solution for returning results. I'd say WPF is several steps up from Silverlight,
unlike your initial claim.