Already been covered.. but now it's on the Google homepage.

http://img508.imageshack.us/img508/9318/googlesignuptj8.jpg

http://maps.google.com/maps/mpl?moduleurl=http://maps.google.com/mapfiles/mapplets/elections/2008/us-voter-info/us-voter-info.xml#utm_source=google&utm_medium=link&utm_campaign=hpp&utm_term=voterinfohpp

Here's a video with actors and other people promoting the URL:

http://www.youtube.com/watch?v=VhDRVKDcXQo

It didn't work for my address. But that is probably because its a new address that hasn't worked yet in Google maps. I expected it to at least give me Minnesota info even if it couldn't map my address.

Google also has a Voting Onebox:
http://farm4.static.flickr.com/3244/2989781390_61227d1252_o.png

Found this ad on YouTube:
http://m1.2mdn.net/1275935/register_2_300x250.jpg

leads to:
http://maps.google.com/maps/mpl?moduleurl=http://maps.google.com/mapfiles/mapplets/elections/2008/us-voter-info/us-voter-info.xml