On the internet it seems the term 'troll' is often directed at someone who is simply expressing an opinion which is different from others in that topic.
It seems to me that society is heading in the direction of not being able to express ones opinion if it offends anyone or expresses anything negative in any way.
There has to be an allowence for someone to express their true honest opinion even if it does go against the thread and general feeling of the topic, as long as they are not abusive towards an individual(s) or saying contradictory and inflammatory things just for the sake of it.