I usually have my shirt hanging out, but sometimes I do wear them tucked in.
I don't follow the crowd, so I wouldn't care. It annoys me people just follow the crowd without questioning it. So the answer is no, but I sometimes tuck my shirt in, anyway.
No. I wear what I'm comfortable in, not what other people think is "cool". Plus, there's nothing wrong with being a nerd. I'd much rather be a nerd (otherwise known as my current self) than some idiot who judges people based on their clothing.