It throws that up after you vote, presumably to make you broadcast this very important poll to the universe of rapt followers we all have. I didn't get the impression you actually have to do that to vote, though, since it pops up afterward. It at least gave me the impression that I voted even though I dismissed it.
The popup says "Please log in to ensure your vote is counted."
The Twitter auth also includes the ability to post tweets for you, although the popup says "We won’t post anything without your permission." Didn't I just give them permission if I authorize them to use my account? No thanks.
