Hi Craig Cote,
Our controls are XBAP compatible and you should not have any problems running the RadCarousel, or any other control, inside a browser. You may visit http://www.telerik.com/demos/wpf/
to see the XBAP version of our Quick start framework in action.
Could you give us more details about any exceptions or errors that you get when you try to run the RadCarousel in XBAP?
the Telerik team