I've seen all the guys in that Leeroy video a few times. I killed a couple of them too.
They are very friendly, though, so I felt bad.
I hit level 54 last night and finished Zul Farrak. I was the only one with the mallet to hit the gong for Gahzrilla and everyone was all "hit the gong hit the gong hit the gong" so I did and after we killed Gahzrilla, the priest was all like "why'd you hit the gong when I was out of mana?"