Here Dan Fernandez explains the technical reason Microsoft claims TestDriven is in violation of the EULA.
I had not understood how much of a hack the integration is. Hijacking a process and injecting code is not something you do by accident.
So my rule is in favor of Microsoft, but I hope they can solve it without taking TestDriven out of business.
This article is revisited here.
There is an ongoing conflict between Microsoft and Jamie Cansdale regarding TestDriven.NET.
I think Microsoft is really wrong here. Is anybody really going to buy one of the non-free Visual Studio SKU’s because they want TestDriven to work? The companies that are so cheap that they don’t use the ‘real’ Visual Studio SKU’s now will probably not buy them anyway. It is still possible to run the unit test outside of Visual Studio so the cost isn’t justified for TestDriven alone.