A rise of subscriber numbers is almost to be expected following big events like BlizzCon, and big announcements like the upcoming expansion Warlords of Draenor. It's a small bump, but the number is still higher than even the 7.7 million subscribers reported in the second quarter of 2013. Subscriber numbers seem to have leveled off entirely in 2013, with the one dramatic drop for the year being the 1.3 million lost in the first quarter of 2013.
With a new expansion on the horizon, a free level 90 to those that pre-order said expansion, and pre-orders set to become available soon, we may see another rise at the next earnings call. New expansions have a tendency to lure back old players, and garner the interest of new players as well. We'll have to wait and see how the game performs in 2014.