Gah, it infuriates me when someone uses this term. It's waaaaaaaaay too overused and is horribly stupid. The simple "FAIL!" is around the same level, for me.
It wasn't THAT bad when it was only used on the internet occasionally, but now it's often used both on the internet and in the real world. I die a little bit inside when I hear one of my mates say that, or just random people on the street... horrible.
Anyway, any terms that you feel are overused and annoy the living shit out of you?