How does your online persona differ from your real-life persona?
Tough. I try to make my online persona in the BBS as close to "me" (that's why I sign w/ my real name, my avatar pic is one of me, etc...) I think the main difference is going to be that my body language, look on my face and tone of voice is missing here - which because I have no inner monologue, tends to play poorly when people say ignorant things in my general direction.
My team of developers that I lead often call me, "the jerk/asshole (affectionately - because they realize my personality directly makes their jobs easier)" - with the two terms used interchangeably, and that's because
especially at work, I say what I mean, mean what I say and if something is stupid or a person has demonstrated themselves as being incompetant I have zero compunctions with proclaiming as much.
However, I'm still just as verbose in real life.