A troll is typically someone who joins a forum for no other reason than to post in a purposefully inflammatory manner in order to elicit reactions from other members. They usually have some form of agenda and crave the attention even if it is short lived. I'm not sure it applies here, but the "I'm a busy person, yada yada yada....." in their defense is usually in the Who, Me? I'm Not a Troll Playbook.
Here is Wiki's version:
[url]http://en.wikipedia.org/wiki/Troll_(Internet[/URL])
OK, thanks!