Songfacts®:

• This song was co-written by and produced by Max Martin, who was behind the artist's prior hits "Who Knew" and "U And Ur Hand."
  
  Pink told the story of this song: "'So What' was a joke. I heard this beat from Max Martin. It's such a fun beat, so fun. And I was actually kidding when I said, 'I guess I just lost my husband, I don't know where he went.' Ha ha, that's really funny. Let's keep it and it just kind of went from there. And it just got more and more wrong. The more lines we wrote, the wronger it was. And we kept it because I don't really care. I don't think about the consequences when I write songs and now I am regretting every second of it. No, I'm not."
• The video was directed by Dave Meyers, who previously worked with Pink on clips for "U + Ur Hand" and "Stupid Girls." The latter won the 2006 MTV Video Music Award for Best Pop Video.
• In this song Pink makes several references to her relationship with her estranged husband, the motocross racer Carey Hart. They separated after his rumored infidelity. Pink is rarely subtle in these matters, and lays it out in the first lines of the song: "I guess I just lost my husband, I don’t know where he went, so I'm gonna drink my money, I'm not gonna pay his rent."
  
  Instead of wallowing in the sorrow of the breakup, she was choosing to enjoy the spoils of her fame, as being a Rock Star without attachment has its advantages. Pink points out, however, that the song is not entirely biographical.
  
  Pink and Hart eventually got back together, and had a daughter named Willow in 2011.
• In the song's music video, Pink is shown riding down a Los Angeles street on a lawnmower. She wrote on her MySpace blog: "This video was too much fun. If you ever get a chance to drive a lawnmower down Sunset Blvd. – I highly suggest it."
• This was Pink's first solo #1 on the Billboard Hot 100. The only previously time she had topped the chart was via the 2001 remake of Labelle's "Lady Marmalade" with Christina Aguilera, Mya and Lil' Kim. The song got a bump when Pink performed it on the MTV Video Music awards, where she used a soundstage as part of a memorable performance where she slid down a rope and blew up a building. Pink stayed in the news when she expressed her political views regarding US vice presidential candidate Sarah Palin, stating: "The woman terrifies me."
• In the UK this leapt from #38 to #1 in the singles chart, the second biggest jump to the top in chart history. The record is held by DJ Otzi's version of "Hey Baby," which with one leap went from #45 to #1 in 2001.
• Carey Hart appeared in the song's music video. Pink commented: "At first I was kind of irked because everyone was like, 'Well, wait. I thought the split was amicable and now she's talking s--t about him?! What the f---?' It's hypocritical.' But once everyone saw the video and saw that Carey was in it, it shut everybody up, which was lovely." She added: "Carey hadn't heard the song before he did the video. That's how much he trusts and loves me. He pretty much just rolls his eyes, throws his hands up in the air, and hugs me. He gets it. He gets me. It's nice."
• This won the prize for the Most Addictive Track at the 2008 MTV Europe Music Awards. It was also named Best Video at the 2009 MTV Australia Awards.