If you are familiar with the Fakes Framework that was previously introduced with Visual Studio 2012, you may already know that it was exclusively available to other development teams entitled to Visual Studio Ultimate Edition.
Unfortunately, those development teams that were entitled to Visual Studio Ultimate Edition were a rare and elite group indeed.
In fact, most Microsoft Partner companies/organizations are only entitled to Visual Studio Premium Edition, therefore, a mocking framework such as the Fakes Framework would be completely unavailable to potentially millions of developers.
Fortunately, with the release of Visual Studio 2013, Microsoft has changed their tune in regards to the availability of the Fakes Framework. It is now available with even the Premium Edition of Visual Studio! Yippee!!
Here is a feature comparison available across all of the various Visual Studio 2013 editions:
Below is the feature comparison for Visual Studio 2012 (where Fakes was notably absent in Premium edition):
It is good to know that Microsoft is listening to the feedback from the development community and subsequently making these requested changes to their feature sets in Visual Studio.