Presidential Electors Vote Today
You didn't really vote for President on November 4. In accord with the indirect design of the authors of the U.S. Constitution, back in the days of still-primitive communication and transportation and drastically restricted electoral franchise, you actually voted for a slate of Presidential Electors in each state and D.C. Today those 538 people (one for each member of Congress, plus three from the District of Columbia) will meet and cast the actual votes for President and Vice-President. A majority of the states require them to vote for the candidates they were pledged to support, and only very rarely does anyone do otherwise. (One John Kerry elector voted for John Edwards instead in 2004, for example.)
The electoral votes cast today will be counted by the new Congress in January. Barring an isolated protest vote, Barack Obama and Joe Biden will each get 365 votes to McCain's and Palin's 173. [And no, Palin won't be the first woman to get electoral votes. Democratic Vice-Presidential candidate Geraldine Ferraro did that ahead of her in 1984.] Then on January 20, the new administration will begin, and Americans and the world can breathe a huge sigh of joyous relief.