There have been reports of this happing ever since Steve announced the switch to Intel. But as far as I know, the actual running of OS X to run on a PC is still a hack and probably illegal, anywhere in the world. Apple have said they won't support it and probably can't stop it from happening, but sporting advertizing with this may be more than Apple will accept.
So, I'm not sure how valid the last phrase in the article might be. "PC World hasn't got itself completely in a twist." We'll see.
They're not actually running OS X. They're just trying to make the machines look nicer