The February CTP of the runtime and development components for WinFX is now available. Realize that since WPF is still a work in process, there are some changes to namespaces, syntax, etc. For a good perspective on the changes check out some posts by Tim Sneath and Rob Relyea about them. Also, Rob has a tool that will be useful in upgrading any XAML you might have lying around from pre-Feb CTP.