I'm going to go with the rest of the bandwagon and say no, I wouldn't be creeped out.

Say I've been watching a bunch of TV shows about scientific developments, because I am interested in those things. I also happen to be an environmentalist, and really hate Big Oil. Just last week, hypothetical me watched "Who Killed the Electric Car?" and was very interested, so I did some Googling around and reading of Wikipedia (in Chrome). Google knows everything I do, and Google knows that I would be a target audience for an electric car. If I saw an ad for a reasonably-priced, powerful, electric car, then I would want to buy it. And I want to see that ad so I can know about it.

Advertisers could use Google's massive datamining to bring this to a "whole new level", as you say. They will be able to do so much more, and target so many more ads. Oh no! I'll have to put up with ads for things I actually want! I won't see those Blackberry ads that keep repeating the same two bars of a Beatles song! How will I ever survive?

The only scary thing about Google owning my life is the worry of their servers failing. But I trust their computers more than I trust mine.

Good thing they have it. It's at 0:33:20 in the big fat video http://wave.google.com/help/wave/about.html#video.

Have a receipt the following way: It says "Obama", "McCain", et cetera, and a bunch of bubbles to the left of the names. The receipt has the bubble of your vote colored in. In this way, it's readable by both humans and computers. But the ballot itself doesn't have to work that way. Just the receipt.