File under: WTF and DIDN'T SEE THAT COMING. Remember the Late Show ad starring David Letterman and Oprah Winfrey that aired during the 2007 Super Bowl? Well, they just did a reprise... with the addition of Jay Leno. Video, inside.

According to Alex Weprin, the ad was filmed earlier this week at the Ed Sullivan theater, and Leno was in attendance.

For reference, here's the 2007 ad.

Update, 7:45 PM ET: Winfrey confirmed via Twitter moments ago that the ad was filmed at the Ed Sullivan theater on Tuesday night, and that all three of them were in attendance.

A screengrab of Winfrey's tweet:

Update, 10:20 PM ET: New York Times late night guru (and The Late Shift author) Bill Carter has posted an extensive article that talks about how the whole ad came to fruition—from planning to execution—and it's quite an interesting read. [CLICK HERE] to read it in full. A couple of noteworthy passages, below.

On how it went down:

The spot was shot last Tuesday afternoon, under the strictest of secrecy which involved both Mr. Leno and Ms. Winfrey flying in surreptitiously to New York, and arriving incognito at the theater, while Mr. Letterman was in the midst of taping his show for that night. It also involved Jay wearing a disguise: hooded sweatshirt, glasses and faux mustache. If you happened to be on Broadway between 53rd and 54th street last Tuesday about 4:15, you might have seen a man fitting that description slip into the theater by a small entrance under the marquee.

On the planning:

As Mr. Burnett described it, Mr. Letterman had the idea to invite Mr. Leno to participate, playing off a similar ad he put together with Ms. Winfrey the last time CBS had the Super Bowl in 2007. "Dave wrote the bit himself," Mr. Burnett said. "He just thought: it's the Super Bowl, you're supposed to entertain people."

Steps were taken to contact Ms. Winfrey, who agreed immediately, Mr. Burnett said, and then Mr. Leno. Mr. Burnett said he spoke with Mr. Leno's executive producer, Debbie Vickers. "She asked if this was for real and then she laughed for about 10 minutes," Mr. Burnett said.

Mr. Leno quickly agreed, but the idea had to be passed by the top NBC executives, including the chief executive, Jeff Zucker. Permission was granted.

Mr. Leno was able to get Tuesday free – NBC had rearranged its schedule to pre-empt his 10 p.m. show that night - and took the NBC corporate jet, Mr. Burnett said. There seemed little chance though that Mr. Leno could sneak into Mr. Letterman's theater unseen, so the idea was hatched to try to sneak him in during a live taping - in disguise.