How to open DGML file in Visual Studio 2010 Professional

How do I open a .dgml file using Visual Studio 2010 Professional so that I see the DGML graph visually? I have read here that VS 2010 supports DGML viewing, but whenever I drag my file into Visual Studio I am presented only with the X开发者_如何转开发ML editor.

Correct, DGML is available only for Premium and Ultimate.

From all that I've read (e.g. there, or there), I suspect that DGML is not available at all in the Professional edition of Visual Studio 2010.

You'd most likely need Visual Studio 2010 Ultimate. It seems DGML is one part of Visual Studio 2010 Ultimate's "Architecture" features.

It also seems as if DGML was available in a Beta version of Visual Studio 2010. (IIRC, the Beta version was an Ultimate edition.)