Sean Penn arrives for the White House Correspondents Dinner Saturday. (Alex Brandon/AP)

(**Read more Monday a.m.: Sean and ScarJo share love with press**)

It was a smoke break, we’re told (they did return). And a tacit confirmation, in front of a room full of journalists, of a relationship the two have diligently non-commented on. And the reason why, for all the trendy grumbling about the event, official Washington can’t quite give up on the annual White House Correspondents’ Association dinner.

Yes, the celebrity sightings. Why are these people here, at a big media-political dinner, the erstwhile Nerd Prom? For just one moment, don’t ask why -- just look.

During the receptions that precede the dinner, a couple of the Saturday Night Live guys -- Bill Hader, Andy Samberg -- pushed their way through the crowded hallway. A woman barely five feet away faced them, clutching a camera, and shrieked, “oh my God!!!”

And yes, she was an official invited guest. Or maybe she was reacting to Jon Hamm, a few feet to their left, who was getting a lot of that. Sen. Scott Brown stopped by the “Mad Men” star’s table for a lengthy chat. “He played me on Saturday Night Live,” the senator explained to us.

Who did CNN place at its best table, the one right up by the presidential podium?: Mila Kunis, Wolf Blitzer, and Paula Abdul. So now you know.

Michael Stipe carried a man-purse.

Now, what you really want to know: Donald Trump’s hair. No mere combover; in person, we see a more elaborate construction. It’s like a thatched roof, or a woven basket. (**read more: Donald Trump vs. Sarah Palin at WHCD weekend **) No one punches the Washington Post’s controversial guest, at least not in the early part of the evening. Cal Ripken stops by to chat pleasantly. A lot of ladies in shiny dresses line up to have their picture taken with the Donald.

There’s more, but we want to listen to the speeches, and then go to the after-parties. We’ll regroup tomorrow.

P.S. Penn and ScarJo left the Vanity Fair/Bloomberg party holding hands; she wore his jacket.

Read also: Obama, from serious to silly, 5/1/11

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