MMO-Champion is reporting that the World of Warcraft Legion expansion is due out on or before September 21, 2016. In addition, the standard edition of Legion will run $50 with the digital collector's edition coming in at $70 with a level 100 boost included and a week's early access to the new Demon Hunter class.
It appears that the image released came via an error on the Battle.net site that has since been taken down but not fast enough. While the date appears to be much further out than many have hoped, it is a placeholder and gives Blizzard room to release Legion earlier than the date mentioned.
There is a lively discussion at both MMO-Champion linked above and on the EU Battle.Net forum.
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