Applied with discretion and thoughtfulness it's a useful tool, but in the hands of an overly snarky or bad-tempered group it can certainly be abused--we are talking, of course, about the group vote kick option. Most of the time when I run group content I don't even remember it's there, but occasionally there's that one person
who won't stop butt-pulling adds before the tank is ready, or who just can't seem to resist spewing a never-ending stream of gross and offensive epithets, or someone logs off and just doesn't ever come back online. When that happens I'm very, very grateful for vote kicks. Sometimes, unfortunately, it gets applied less sensibly; I've heard of players being kicked for every reason from their choice of toon being disliked to not having "enough" heirloom gear equipped, and situations like that can be infuriating.
When I stopped to think about it, I realized that I have never myself been kicked from a group. I'm sure this is mostly due to the fact that I'm not a huge dungeon runner, so I'm not in random groups very often, but also at least partially because when I do run group content I tend to play a healer. Kicking a healer, while sometimes necessary, can also occasionally result in a very bored group sitting around for a while waiting for a new one, which is no fun. Sometimes people don't believe me that I've never been kicked, but I've met plenty of players who also say they haven't, either, so I've never thought myself particularly unusual, but I still I count myself as being lucky in this respect. How about you, though? Have you ever been kicked? And, perhaps more importantly, was it deserved or were you the victim of a trigger-happy kicker?