Firelands raid will not be in Patch 4.1
What I've been suspecting for a while is now confirmed, Firelands will not be included in patch 4.1. This is why you aren't seeing anything about it in the patch notes or on the test realms.
For more details on the decision, read the Full Article on Eurogamer.net
Blizzard has told Eurogamer that the Firelands raid – the next tier of endgame raiding progression for the MMO – will not appear in the next patch, 4.1, as it had previously planned.
In an interview at the Game Developers Conference in San Francisco, lead producer J. Allen Brack said that players were not sufficiently advanced through the raid content that shipped with third expansion Cataclysm in December to handle the challenge of Firelands. He also suggested that Blizzard was thinking of creating "smaller" content patches for World of Warcraft.
"We feel like the player base isn't really ready for the next raid yet," he said. "And that led to some changes where Firelands is now actually going to be in 4.2."
"Our plan is to package... features into smaller content updates and to release them as soon as possible, rather than wait and release larger updates more infrequently," Blizzard added in a statement.
[...]After the interview, Blizzard gave Eurogamer the following statement about the decision to remove Firelands from patch 4.1.
Patch 4.1 - PTR Notes Update - March 3