Insiders tell us the “Late Show with David Letterman” taping is happening right now with Pres. Obama and it includes the Top 10 reasons Obama came on the show.

They include: Obama thought it would be fun to see someone else get heckled; the appearance was part of a cash for clunkers program; Obama needed a place to stay until check-in time at the hotel and the #1 reason is that Obama wanted to congratulate Letterman on his big Emmy win last night (“Late Show” lost to “The Daily Show.”)

> More: They talk about healthcare reform, Afghanistan, Iraq and the economy. Letterman: “Your job is more difficult than my job, that’s what I learned here tonight.”

On race, Obama says: “It’s important to realize that I was actually black before the election.”