As a previous admin, you know that there are cases of friendly "flaming" (which actually consists of jokes) between two players that could be seen by other individuals as blatant personal attacks or rude insults. In the case of newer individuals to the forum, they could see such posts and misinterpret them into the idea that flaming is allowed, which leads to more actual flaming.
I know what it's like to pull off such jokes between group mates, but it would be best if some of the more... ambiguous remarks which can be seen as flaming by the rest of the community were kept somewhere private, such as MSN / Chats / Ingame CB.