With the launch of the Warlords of Draenor expansion pack, World of Warcraft's player base has spiked, totalling more than 10 million subscribers.
Back in October, prior to the expansion's release, the World of Warcraft player count was sitting somewhere around 7.4 million. According to an announcement from Blizzard however, within 24 hours of release, over 3.3 million copies have been sold, and the subscriber-base has passed the 10 million player mark.
This has become a pattern for Blizzard, with each expansion release bringing back a large number of players. The same thing happened when Mists of Pandaria released, so this might be one of the reasons why Blizzard is trying to annualize the franchise. What these numbers also show is that World of Warcraft has no problems when it comes to its monthly-subscription model, and isn't going away anytime soon.
While the numbers are genuinely impressive, it seems Blizzard has yet to learn how to deal with a massive influx of players. The expansion release was beset with a multitude of problems, some of which, are fairly uncommon for the publisher. These issues prompted the studio to reward players with 5 days of free-access.
Warlords of Draenor is now being released in South Korea, China, Taiwan and Macau, which may further increase the subscriber pool. It's also worth noting that this year, World of Warcraft is ten-years old, and still going strong.