Really, wild guesses and speculations:

(1)John McCain recovers to win the Republican nomination.

(2)Ron Paul does better than expected, and is one of the last three candidates left in the race. He then runs a third party campaign, drawing enough support from McCain, especially in the Mountain States, to throw the race to the Democratic nominee.

(3) The U.S. will enter a recession in the third quarter of 2008

(4) which will also be the bottom of the housing market in nominal (but not real) price terms.

(5) There will be a surprise Supreme Court vacancy.

Check back in December 2009 to see how I did.