http://www.gameinformer.com/b/news/archive/2015/08/04/world-of-warcraft-subscriptions-plummet-to-5-6-million.aspx

The next World of Warcraft expansion can't come soon enough for Blizzard.

Today during the Activision earnings call the publisher revealed that number of subscribers for its popular MMO have dropped to 5.6 million, continuing a downward trend for the title. Since the high water mark of 12 million subscribers in mid-2010, the number has vacillated between expansion packs, but we haven't seen a number this low since 2005. More than 10 million users were subscribed last November, when the Warlords of Draenor expansion released. That number dropped to 7.1 million in May and continued to plummet to its current level.

Six days ago Blizzard announced plans to reveal a new expansion for World of Warcraft during Gamescom this week.