Some stories I like to reply on, but somebody has already typed in what I wanted to say. I could reply with "I second that" and sometimes I can't help myself and do that, but I would much rather have a button called "I agree", which I could push to say that I agree with the comment. Or an "I second that" button. Then you could just show "x poeple agreed", instead of having to hide all those lame "I second that" and "right!", etc. replies I sometimes make.