Wiki is not a message board. Wiki is an encyclopedia. You are posting on the message board. It is "message board" singular in the TOS. You're just making stuff up now.
Wiki is a social media used to bring people and content together. Allowing for collaborative effort that includes messaging. There are about 50 wiki software package available including open software. The issue with the version of wiki at Aces High is that the different authors failed to keep there contributions updated. As for the TSO the term message board refers to and covers all forms of written messaging within the game, including BBS, Wiki, PM and text boxes. It doesn't have to be plural.