Johnny Mac Aces with Ari Gold; President Obama Has a Burger; The Kills’ Jamie Hince Hangs with Joan Jett at Kenmare; Sean Penn Gets Punky at Aziza for Haiti

We hope Sean Penn didn't try to bring his own bagel to Aziza.

* Tennis great John McEnroe and son Sean did karaoke with Entourage star Jeremy Piven at Cafe Habana in Malibu. [NY Post]

* Tina Brown threw a luncheon at La Grenouille for Ms. Gloria Steinem, who had some less-than-choice words about they-whose-names-that-start-with-a-K-shall-not-be-named-here. [NY Daily News]

* The POTUS had a burger at Ted’s Bulletin in D.C. and left a fat tip. Nice! [TMZ]

* Ethan Hawke was spotted at La Bottega with his nanny wife and new daughter, whose name is Indiana, which also happens to be the name of my German Shorthaired Pointer. He likes Italian fare also. [NY Post]

* The other fresh prince of Bel-Air, Alfonso Ribeiro, chatted up the papparazzi outside Katsuya in Hollywood after dinner. [TMZ]

* Spicoli and Punky Brewester, aka Sean Penn and Soleil Moon Frye were at Aziza dining to help Haiti. [Tablehopper]

* Jamie Hince, aka Mr. Kate Moss, hung out post-gig at Kenmare in NYC with Joan Jett. ScarJo was also in the house. [NY Post]

Jonas-about-town Joe supped with a mystery girl at Susan Feniger’s STREET in LA. [PerezHilton]

* N*SYNC’s Lance Bass sang “Happy Birthday” to Joanna Garcia-Swisher (of, um, Reba?) at The Darby, before moving on to Butter. I hope he also sang “It’s Gonna Be Me.” That’s a banging song, even 11 years later! [NY Post]

* Speaking of celebrity sightings, celebrity magnet The Waverly Inn in Manhattan is now on OpenTable. If you see any bold-faced names, please be cool. Thank you. [Grub Street NY]