Why not -1 button?

So apparently google have added a +1 button to the search results. Why not a -1? I'm not sure exactly what this is supposed to achieve - yet more ways for spammers to skew the results? I'm already a bit wary of google giving me my own private view of the internet, I hardly want that increased. And often what you're trying to find is the stuff that doesn't come up on the front page now - it seems this would only make that worse.

Just more clutter I don't need or want which simply slows down the page loading.

They also seem to have fucked up the mail client by making a section of the screen not scroll. Which makes it unusably slow and even uglier than it's already ugly forebear. So I guess I will have to go to basic HTML mode now. Which is a pity because I use the chat thing to find out when drinks are on.