Unusual XNA Tools Licensing

In the Microsoft XNA EULA, I found the following restriction: You may not use the software to develop programs that run on any platform other than the Windows, Zune or Xbox 360 platforms

I’m no lawyer, but this sounds like very poor wording. Does this mean that all source code developed with XNA Game Studio is restricted to use on those platforms, in perpetuity? That would mean that it couldn’t even be used on a future, new Microsoft platform!

This seems to me to be unreasonable and probably unenforceable.