Facebook Live

Rock stars and even former presidents have taken to Facebook to connect with the masses, but never before has an acting president appeared live on Facebook. Until now! President Obama will appear live on Facebook Wednesday, April 20 at 1:45 PDT (4:45 EDT).

CEO Mark Zuckerberg and COO Sheryl Sandberg will sit down with the president, who plans to discuss current economic conditions and "tough choices we must all make in order to put our economy on a more responsible fiscal path."

Facebook will be selecting user-posted questions to include in the interview. To submit your question, post it on the event's Facebook wall, or more privately via the White House's official site.

If my Gaga love is second to any artist, it's Katy Perry. Today, she headed to Facebook HQ in Palo Alto this afternoon for a Facebook Live chat, and revealed that her upcoming tour will feature a whole lot of geeky goodness. "I feel like I'm a child of the Internet," she says. So, she's incorporating some of the best online features into her upcoming shows.

Katy is partnering with Facebook to encourage fans to check into her concerts. She's also planning to encourage Twitter and Facebook usage during shows, displaying tweets and status updates in real time on screens.

After being asked several questions by Facebook's Randi Zuckerberg, Katy commandeered control of Zuckerberg's MacBook Pro, choosing her own fan questions to answer. In addition to questions about the tour, she shared some of her favorite new songs (Taylor Swift's latest), upcoming tour stops (Mexico and Brazil, among others), and also showing the Facebook audience her awesome pair of platform shoes.

Celebs like Conan and Kanye have wandered the halls of Facebook HQ, but for the first time, an ex-president will be making an appearance.

Former President George W. Bush will make Facebook HQ the next stop on his promotional tour today and will be livestreaming a discussion about his new book, Decision Points. The 43rd president may not be the most popular POTUS on Facebook (that title goes to current President Obama, who currently has over 16 million fans), but George W. has gained an impressive 600,000 "likes" since he opened his page this past Summer.

Find out where to tune in, and how to ask your questions, when you read more.