See the announcement, made minutes ago, HERE. In summary, a new “Adventure Pack” called The Savage Coast of Turan is slated for August release, and will tie in with the upcoming movie, albeit set some 20 years later.
No word yet on how “Adventure Pack” compares to “Expansion” in terms of the amount of content being offered, but it will include “all new encounters, the massive new area of Ardashir, new dungeons and raids as well as new armor sets and monsters.” More details as they are revealed.
UPDATE: Looks like this is on the scale of “Adventure Pack” more than expansion, but large at that. It’ll focus on the level 50-80 range and will include locations from both the film and the Howard stories, including a new raid, the Temple of Erlik, and multiple new instances for both solo and group play. It also sounds like there will be no increase to the level cap and no new race. There are interview HERE, at Eurogamer, that goes into some of this detail.