Call of Duty: Online is real, although the chances of you playing it if you live outside of China seem pretty slim, at least for the time being. Bringing together some of your favourite maps from Modern Warfare and Modern Warfare 2, Call of Duty: Online will be a free-to-play way of reliving some of the franchise's multiplayer highlights without having to shell out on old games with a reduced user base and rampant cheating.
To be available only in China, Call of Duty: Online will apparently take popular game modes from Call of Duty's past and remodel them on China's tastes. How exactly they'll change things is as of yet unannounced, but since playing will be a pain for almost everybody on the planet, I don't suppose it matters all that much.
Of course, this being Call of Duty, people are already attempting to run it down. Apparently Activision can't even give it away for free to some people, although I'd be willing to bet this'll be a huge hit if it ever comes westward.