According to a statement from Blizzard on Eurogamer
, patch 4.1 will not contain Firelands and the associated raid content. Lead producer J. Allen Brack cited the fact that players hadn't sufficiently progressed through the current tier of raid content as the reason for this decision. Eurogamer provides the quote: "We feel like the player base isn't really ready for the next raid yet," [Brack] said. "And that led to some changes where Firelands is now actually going to be in 4.2."
This is a step toward much smaller (and faster) content patches, much as we had back in vanilla WoW
. Blizzard could release a small set of features far more rapidly than the current "monolithic" patches. Firelands and its associated raid content will now be included in patch 4.2. Patch 4.1
will entirely focus on the return of Zul'Aman and Zul'Gurub.