For all of you that raid regularly since Ulduar opening, last week and even more this weekend made it clear. Ulduar nerf has started.
Two waves of nerfs have already hit Ulduar, detailed on MMO Champion on the 29th and 30th of April. First ones seamed to be more fixes, balance nerfs, there are detailed here. But the second wave, linked to patch 3.1.2, is a clear downgrade of Ulduar difficulty. I first thought they were only lowering a bit 10-Man difficulty, which was a bit too high compared to 25-Man for me. But now the nerfs hit everything, 10-Man and 25-Man alike, from the first bosses up to Vezax (last boss before Yogg-Saron).
I'm a bit sad to see a difficult raid instance that was promising weeks of fun to master and finish being nerfed to a Naxxramas plus. I'm expecting more nerfs to come in the next weeks or at most months. If they start so soon, they won't stop, finally nerfing Ulduar down so that anyone can go there, without need of guearing or anything.
Let's have fun as long as it lasts. Soon only hard modes will promise any sort of challenge (at least these ones are not nerfed).