Basically all non-netbook laptops sold within the last 6 months have a CPU that has on-die video decoding, but many (though still a minority) desktops don't. I'm not sure why you're bringing MCMs into the discussion, those were the norm in Intel laptops for about a year before that with the Nehalem chips in laptops, but right now the only MCMs being sold are server chips which don't have GPUs at all, but rather require more silicon than can economically be produced in one piece.