Not that it was happening, but rather that it added a really strange sound effect to my Bloodrage and Berserker Rage abilities. My wife described it as sounding like the mutant offspring of an orc and a murloc howling in anguish, and she's not far off. After a while I realized I recognized the sound as being the same one that plays when Horde shamans use Bloodlust.
Now, I don't know why, but while I accept the sound when it comes out of an orc, I have a really hard time hearing it when my human pops bloodrage... which he does a lot, since you know, needs more rage and all. This is reminiscent of the previous patch with the unexpected change to Whirlwind (also a sound effect change) and it makes me wonder every time if I just wasn't listening or if it's an actual change.
Furthermore, it always makes me stop and think about just how much development work goes on for things like new music in inns, new sound effects, a new pet model... these things all add up and it's a lot of work if you stop and think about it.
Have you noticed any other changes, undocumented or just stuff you didn't really think about?