there's also no way that I can see that this can be fixed (in its current implementation)...

if you somehow had a history of highly voted comments, you would need all the other comments to get context, but then some of those comments might be already be downvoted to hell, etc...

also, by their nature, chatroom messages are short and often only address one part of a conversation. I don't see how there will be enough time for users to provide a meaningful upvote/downvote for anything not obviously inflammatory.