Q: I thought Wikipedia wasn't allowed to have articles on itself, how can this be an article?
A: Wikipedia is allowed to have articles on verifiable and notable things that are covered in reliable sources. There are already several articles on subjects primarily notable for their involvement with Wikipedia: English Wikipedia, Internet Watch Foundation and Wikipedia, Simon Pulsifer, Michael Snow (attorney), Wikipedia Review, and Essjay controversy.
Q: Why can't I add something about this [case, arbitrator, editor]?
A: Content must be covered in reliable sources for inclusion in Wikipedia. Of the hundreds of Arbcom decisions and dozens of arbs, very few have made the news media.
Q: Why are some of the links external links when they should be internal?
A: Some of the links, such as to the Arbitration Committee page, point at non-mainspace pages. For the benefit of those reusing content, who don't copy the Wikipedia space, externally formatted links are used.