Sean Penn, left, and Scarlett Johansson, right, at the Bloomberg & Vanity Fair cocktail reception following the White House Correspondents' Association Dinner Saturday. (Dimitrios Kambouris/VF11/WireImage)

Washington and Hollywood, in the same room but a different space: Eric Cantor and wife Diana walk the red carpet alongside actress Elizabeth Banks (Jonathan Ernst/Reuters)

ScarJo and Sean let us in on their love, but Washington was otherwise feeling shut out — wallflowers where once we were prom kings and queens. The celebrities who once decorated the weekend now dominate it. (Flanking Wolf Blitzer at CNN’s best table, up by the dais: Paula Abdul and Mila Kunis.) And what used to be a free-form mingle (look, there’s Natalie Portman talking to John Dingell!) has been velvet-roped into submission.

Mila Kunis sits with Wolf Blitzer at the CNN table. (Martin H. Simon/pool image via Bloomberg)

For many rank-and-file journalists and their sources in government, the goal is no longer to get into the dinner but simply into one of the many glitzy sideshow parties. At the Hay-Adams Friday night, every young pundit you’ve ever seen hold forth on cable mingled over champagne and canapes for the “Emerging Voices in Media” party, sponsored by the Brunswick Group lobbying firm. Rodell Mollineau, a longtime aide to Sen. Harry Reid who just left the Hill to run a new Democratic mega-PAC, noted wryly that it was the first year in many that he hadn’t scored an invitation to the dinner.

“Not getting invited,” sighed Terence Samuel, an editor at National Journal, “is a rite of passage.”

Michael Stipe, center, arrives with Thomas Dozol to the dinner. (Jonaothan Ernst/Reuters)

Some cold shoulders we could understand. At a late Friday “First Amendment” party (hosts: National Journal, the Atlantic, Funny or Die, and Impact Arts & Film Fund) throbbing with music and free booze, one inebriated fan asked for a photo with Penn and then turned snippy when the famously prickly star declined. Hostilities escalated: Penn struck the man’s cameraphone and drink from his hand. We’re not sure on the timeline, but, around then, the organizers hastily erected a velvet rope across a section of the room and divided the crowd by wattage.

She’s glowing! A pregnant Alyssa Milano arrives at the dinner. (Alex Brandon/AP)

Luke Russert and Terrell Owens at MSNBC’s after party. (Mark Gail/The Washington Post)

Mills’ media host, David Corn of Mother Jones, leaned in to convey that the car would be coming around in a few minutes to whisk them to the Vanity Fair/Bloomberg after-party.

“Do we have to go?” Mills asked. “Is it better than this?”

Actress Salma Hayek and her husband Francois-Henri Pinault at the Bloomberg Vanity Fair party. (Joshua Roberts/Bloomberg)

Paul Rudd, Rashida Jones, Amy Poehler and Bradley Cooper at the Bloomberg & Vanity Fair party. (Dimitrios Kambouris/VF11/WireImage via Getty Images)

So Matthew Morrison, what prompted you to return to this bizarre affair? “There’s nothing like this,” said the “Glee” crooner, who made his WHCD debut last year. “An incredible combination of New York, Los Angeles, Washington — and amazing finger foods!”

“Excuse me,” his handler interrupted, and then turned to Morrison: “I want to take you over to say hi to Sean Penn.”

Our colleague Dan Zak contributed to this report. Some elements of this story, printed in the Style section of Monday, May 2, appeared in a Saturday posting on this blog.

Full coverage: 2011 White House Correspondents' dinner