I came upon a very interesting post on the vista knowledgebase blog where the author was describing a very unusual behavior that he experienced with Windows Vista. She apparently was running a legit, fully activated copy of Windows Vista and decided to install the upcoming mmorpg game 9 Dragons which is currently in Open Beta phase.
After installing the game and playing for a while a message from Windows Vista popped up minimzing the game in the course of action. The message that appeared told her that her copy of Windows Vista was not genuine. She tried to reactivate the operating system but it would fail although she would supply the correct key that was accepted before.
After uninstalling the 9 Dragons game the activation was again accepted and Windows Vista was activated again.
If this story really holds true it is a remarkable one. Why on earth would Windows Vista revoke the activation - this would be the main questions that would have to be answered.
This pretty looks like a way for Microsoft to revoke the activation on systems that run known pirated keys or install software that would probably try to interfere with Windows Vista core processes.