I think the reason why so many Nintendo fans dislike Matt is not because he's 'anti-Nintendo', but he gives an honest opinion. This is the opposite of the other IGN channels (Xbox, PS3), which hype everything like their console's a non-stop orgasm. This would seem unfair to the Nintendo fan, and instead of blame the other channels for their behavior, they blame Matt for not being like them.
Frankly, I like Matt because he's honest.