Possibly just in order to remind you that it knows your exact age (among other things), Facebook is posting reminders on the newsfeeds of all U.S. users age 18 or older that tomorrow is Election Day, and that they should go vote. Those aren't just empty words: A link in the posting will take people to a Polling Place Locator, with maps. Those who did vote — or enjoy lying about their participation in democracy — can click an "I Voted" button.
As anyone familiar with "Like" buttons can guess, Facebook will tally the number of people who say they voted, showing a total number and telling you which of your friends believes in being part of the process, and which — by omission — are deadbeats who are to blame when the candidates of your choosing totally bite it. In 2008, 5.4 million U.S. Facebook voters fessed up to it. If the number of voters is greater this year, it probably demonstrates greater enthusiasm in Facebook than in the electoral process, but it's certainly a start.
A note about the Polling Place Locator: It's not smart enough to know if you're eligible to vote, whether you filled out all the necessary paperwork and have your address up to date and all that. It just tells you where you should go, assuming you're registered to vote at the address you enter. The service is brought to you, via Facebook, by the non-partisan Voting Information Project. (If you want to do this without the Facebook framework, you look at Vote411's Poll Finder.)
Location-based service Foursquare has also created an "I Voted" badge program. In this case, you "check in" at your polling place to let friends know you voted. Foursquare says that its program is meant to "encourage civic participation" and "increase transparency," by showing who is voting where. The official site of Foursquare's program is elections.foursquare.com.
For more info on Facebook's voting initiative, check out Facebook's U.S. Politics page. And if you're really trying to keep up on the elections, don't forget to join in the Decision 2010 conversation with msnbc.com on Facebook.