Hmmm you have a point. Maybe (and this is a big maybe) he will run for Governor of NY and then try for president in 2008.
Something to keep in mind here is this: If you go back over the last couple of decades and look at the political landscape on the day after a Presidential election, you'll find that the opposing candidate in the next Presidential election was usually nowhere to be seen on the horizon.
How many people were predicting in 1988 that Bill Clinton would be the Democrat nominee in 1992? Or in 1996 that George W. Bush would be the GOP nominee in 2000? How many were predicting in 2000 that Kerry would be the Democrat nominee in 2004?