Instead, Activision Blizzard will use other unspecified "engagement" metrics to talk about the health of WoW. These were not detailed during the earnings call where the announcement was made on November 3.

WoW's 5.5 million subscribers as of September 30 represents a loss of 100,000 subscribers over the past three months. The game's subscriber figures now stand at a nine-year low.

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History shows that WoW subscriber figures increase with the release of a new expansion. So it may not be surprising to learn that Blizzard's new plan for expansions is to release them faster. In order to do this, the game's development team grew in terms of head count, as of October 2014, it's bigger than ever before.