According to Chris Taylor – ‘World of Warcraft’ Lost 1 Million Gamers in Three Months. Is It Over? – WoW has gone from a peak of 12 million subscribers in October 2010 to just 9 million today.
That still makes it the largest MMO on the planet. But if this rate of depletion were to continue, the fantasy world would be a ghost town by 2014.
Still a big number, but I think this illustrates the shift away from PC gaming.