Just a couple of ideas that i came up with as i was posting on another post and decided to get some more direct feedback.
[local] [/local] would make it so that this part of (or the entire post somehow) would be kept to the place where it is posted, for instance news from the west side of the rinth that would most likely never make it's way east side.
[rnd] blah, blar, blarf[/rnd] randomly chooses one of the listed responses and puts it into the post. this would be like if you heard a rumor and then reading it again might give you a varied version of the same rumor.
Interesting, I will give you that...though I'm not sure it would be worth figuring out how to put it in. The IG rumor boards don't currently support anything like this...so this would be a larger addition than some.