Yes there have been some nasty exchanges. Frankly, once a thread gets silly I just stop reading it. The same goes for this forum. Life is too short to pick fights with strangers on the internet.
On a more serious note, however, it is a reflection of a part of NMA's following. NMA is known for its outspokenness and turning gut reactions into songs so it's perhaps not surprising that we are seeing this kind of behaviour. As we're all getting older and more mellow, it's easy to forget that before NMA fans were 'family' they were 'militia'. And militias don't always fight the prettiest wars.
Also, you can't ignore the fact that a number of people bear some grudges (rightly or wrongly) and if they leave one place they will likely pop up again in another. A lot of the behaviour we're seeing on FB seem to be borne out of a level of intimacy and connection with the band that far exceed mine. I guess it's all part of the 'Better Than Them' discussions that we used to see here in the past.
Maybe some more open discussion in a more controlled environment wouldn't be such a bad thing after all. I don't know.
However, I do agree that the group should change its name as it does not represent NMA.