At the risk of sounding like a nutrider, I also agree that MT is a good forum for discussing and learning about other arts, without the nuthuggery, ball busting or a** kissing you find on other forums. Though there are some clicks that have been subjected to scrutiny, I have nothing to do with them, so it's cool with me.
When it comes to E-Budo as someone else mentioned, they're way too much into "If it's not of Japanese lineage, it's not legit" BS.
Whatever forum you go to, it will always be subject to the forum owners base art, so there's always gonna be judgemental opinions concerning other systems. I've yet to see a fully "OPEN" forum that doesn't cater to the owners/moderators art-lineage-Grandmaster etc.