Official White House Photo by Pete Souza via Wikipedia

Here’s the CBS press release:

PRESIDENT BARACK OBAMA TO VISIT CBS’s “LATE SHOW with DAVID LETTERMAN,” TUESDAY, SEPT. 18

 Will Be His Seventh Appearance on the LATE SHOW and Second Since He Was Elected President In 2008

CHEAT TWEET:  President @BarackObama to visit @late_show Tuesday, Sept. 18, 11:35 pm ET/PT! http://bit.ly/U9jxZ8

President Barack Obama will visit the LATE SHOW with DAVID LETTERMAN, Tuesday, Sept. 18 (11:35 PM-12:37 AM, ET/PT) on the CBS Television Network.  

This will mark President Obama’s second visit to the LATE SHOW since his election as President of the United States in 2008 – he last appeared on the broadcast Sept. 21, 2009. Including his appearances when he served as U.S. Senator from Illinois and during his 2008 presidential campaign, this will be his seventh overall visit to the LATE SHOW.

Willard Romney will now accuse the president of apologizing for America to CBS, being a Letterman sympathizer, appeasing Paul Shaffer, and, of course, not wearing a flag pin.