A big source of user feedback when Visual Studio 11 beta was released was the emphasis on “give more space for your content and the second being to draw more focus to that content” – essentially it meant you were seeing a lot of grey in your Visual Studio windows when you were actually using it.
This caused quite a consternation in the user base who responded by saying that they wanted some semblance of colors as that is “central” to the Visual Studio IDE experience.
Microsoft as usual has listened to this valuable feedback from its CORE user base and responded by doing the following:
Provide more visual energy to the appearance
Personally I welcome this.
You can read more about this from the Visual Studio Team blog here: