One of the things that amazed me while reading through the new features we'll find in the final release has the following title: "WPF Interoperability with Direct3D".
But why does this means a lot to me -or should mean a lot to us XNA-based game developers?
If you ever attempted to integrate a D3D-based game/application into a WPF-based project, you may know that one of the hard burdens to surpass to get that job done is called "Airspace", a strict rule that prevents both type of applications to co-exist in the same region of the screen, at least without a simple solution.
And I say simple here because to "bend" this rule a little bit to make the user believe that a real integration exists -meaning, as if there was not Airspace at all in the first place- either you had to use a decorator-pattern-based implementation or a solution where you intercept all windows messages in order to "bake" all pixels rendered by D3D into an image that can be later used by any WPF control ... if you want to know more about this rule and or get one of these solutions or both of them just do a simple Internet search with the words "DirectX WPF Airspace" :)
Well, as this is becoming a built-in feature now, it means that we can stop worrying about finding or choosing the optimum way to integrate D3D and WPF, what in turn means that we don't have to constraint our D3D-based projects to WinForms controls anymore and thus we can let our imagination fly to create a rock-solid kicking @$$ game-level editor using WPF and XNA -specially now that GS 3 integrates into VS2008.
Really great news ... although we have to wait a bit more to get our hands on this feature until the final SP is released ... :)