Joe Belfiore showed Silverlight applications already working on the new Windows Phone - amazing. Some details:
- There is only version of Silverlight - works on the mobile the same way it works on the browser - same core, same programming model.
- Development environment - Visual Studio templates for developing for the mobile - great user experience; built-in emulator, one-click deployment to the mobile; full debugger integration;
- Twitter client - Scott Guthrie developed a Twitter client for Windows Phone in 5 minutes - pooled data from the Twitter service, prepared the items with LINQ to XML and binded the data to a ListBox. Hit F5 and everything was deployed on the emulator.
More on designing Windows Phone apps with Blend comes in couple of minutes.