The End User License Agreement (EULA) for the upcoming Windows Vista was made available by Microsoft about a month ago. You can read obtain a PDF copy of the EULA though Microsoft's website.
It turns out that there are several provisions in the EULA that are unusually restrictive, to the point of being draconian (What? Microsoft licensing is restrictive? I'm shocked! Shocked, I say!). Obviously restrictive EULA's are nothing new, but this is a bit much even according to Microsoft standards. Some of the highlights include being limited to one and only one license transfer, being forbidden to run the Home versions in a virtual machine and being forbidden from accessing any DRM content while running under a virtual machine.
There has been quite a few articles written about this in the past couple weeks; however, I think Scott Granneman's article on Security Focus does the best job of detailing the issues. He also includes a lot of links and references to other sources about this.
If you're considering buying/upgrading to Vista when it's released, I strongly recommend reading this article before you do. I'll leave you with a short quote from Granneman's article:
If you thought that the legal troubles the company faced in the late 90s would perhaps mellow it out, you were wrong. Far from it. The draconian limitations I've discussed could only be enacted by a monopoly unafraid of alienating its users, as it feels they have no other alternative.