I wasn't on here when the Madeleine story kicked off two years ago, but assume it was a total bunfight - the way it was on every other forum I was on at the time.
MN is just reflection of wider society on this one - ie totally polarised, and very open to influence from the media.
On the last forum I was a member of, they had to eventually ban the McCanns as a subject of debate, as it was simply impossible to maintain civilised threads about them, no matter how polite and restrained everybody promised they'd be at the outset. I bet this has been replicated on many other forums too.
I'd be happy to see the story die. I have seen some utterly dispiriting stuff posted about them that makes me ashamed to be an internet forum user at all. I just don't see where further debate could take us - nobody is ever going to change their minds on this, are they?