In all the forums I've been involved in "trolling" refers to somebody who comes along and asks a question where they don't really care about the answer, they just want to stir things up. Or where they make a statement with a lie or a half truth, again to stir things up. The common example is "Which is better, Mac or PC?" They really don't care, they just want to see how big a fight they can stir up. Another might be " is not only cheaper, it's far better than ". (this would be trolling if posted in the forum of product y, but not if it was posted in the forum of product x) The term came from "Fishing for a reaction", or "Trying to bait someone into an arguement".