An extremely weak thread, obviously who posted it has not thought the ramifications through, so let us suppose that Obama (Who I did not vote for) actually resigned.
Biden takes over the Presidency.
Biden with a history of heart ailments.
I doubt Biden's heart could stand the pressure for long.
His replacement? Pelosi.
I may not have voted for Obama, but I will gladly stand up and state 'Long may he reign as the US President', well at least until 2013.