World of Warcraft appears to be shedding players, with Blizzard's MMORPG now only boasting 5.6 million subscribers, a drop from the 7.1 million reported at the end of March. Following the release of the Warlords of Draenor expansion last year, the number was as high as 10 million, so the studio will be hoping that their next expansion - due to be announced tonight at 5pm - will have a similar impact on subscriber numbers.