well from now pretty much every week we get new info/things relating to mist of gymmybears.
i think it would be time to make a MOP subforum where we can discuss the new content. there should be some press event coming up in 2 weeks. where we should hear some thing about.
dungs
raids
new talent system
panda race
challenge modes.
generaly something is put up when there is more confirmed information like you state...watch this space
Content like that is usually just put under WoW General. Subforum is rather pointless as in a while MoP will be the 'current' game and everything is put in WoW general again xD
Also: http://www.deadmen.co.uk/forum/showthread.php?34168-Mists-of-Pandaria Discuss!