Edit: It seems the threats to leave the country may well be the Telegraph's conjecture, rather than Kotick's intent. Either way, he's cheesed off with the government's lack of support for the games industry.
Activision may be taking their ball and jumping on a plane, in response to the government's decision to make it as expensive as possible to make videogames in the UK, despite glee-facedly lying about doing the opposite moments before the election. The Telegraph reports that Bobby Kotick may want to up and leave to friendlier shores, now that there's going to be no tax break for developers. The shy, retiring Kotick explained, "I think it was a terrible mistake. There are so many other places that are encouraging the video games industry."
There's 600 Activision employees in Slough, who have yet to deny rumours that this potential move is really an excuse to leave Slough.