Omitted options notwithstanding, at least some of those people are utterly wrong, even if all of them can claim lots and lots of evidence, and most advocates of any of them seem only to consider people who agree with them to be objective.
I'm not sure how much room for objectivity there even is in the whole debate anymore. It's a religious issue; people have their views on it, most of them are transparently political ("global warming is false because if it is true we'll have to do stuff and that's not libertarian!" "global warming is true because conservatives think it's false!" etc). I really don't think anyone's going to change their mind even if someone hammers out The Truth Of The Matter - and there is one, whatever it is - and I really am convinced by now that most peoples' definition of "objective" on the issue is "this person's conclusions match my own."
I probably can't consider myself exempt from that either, which bothers me.