Someone over at Joystiq's on the ball with their screenshots this morning. They captured a shot of the BBC website reporting that Halo 2 for PC is going to debut on Vista. Interesting....

"In an article that vanished as fast as it appeared, the BBC temporarily reported that the PC version of Halo 2 is to debut on Windows Vista. We managed to get a screen grab of the link (pictured and highlighted above) to the news story just before it changed."