The two were photographed at Los Angeles' Chateau Marmont Wednesday, fueling weeks of rumors that the "Your Body Is a Wonderland" singer is the "I Kissed a Girl" gal's rebound from ex-husband Russell Brand. Reps for the pair did not respond to ABCNews.com's requests for comment.
Despite some epic relationship blunders, Mayer has managed to date an impressive array of Hollywood's pretty, young things. Let's take a look at the club Perry might be a part of:
Swift's brief relationship with Mayer was so bad, she allegedly wrote a song about it. Her 2010 hit "Dear John" includes such lyrics as "You paint me a blue sky and go back and turn it to rain" and "Don't think I was too young to be messed with?" While Swift never confirmed that the song was about their brief romance, earlier this year, Mayer told Rolling Stone that he was "really humiliated" by the lyrics.
"It made me feel terrible," he said. "Because I didn't deserve it. I'm pretty good at taking accountability now, and I never did anything to deserve that. It was a really lousy thing for her to do."
Before Swift, Mayer dated Aniston on and off between 2008 and 2009. His penchant for oversharing on Twitter upset the "Friends" star. "There was a rumor that I'd been dumped because I was tweeting too much," he told Playboy after their breakup. "That wasn't it, but that was a big difference. The brunt of her success came before TMZ and Twitter. I think she's still hoping it goes back to 1998. She saw my involvement in technology as courting distraction. And I always said, 'These are the new rules.'"
Ah, but rules change. Mayer famously "quit" Twitter in 2010, abandoning his 3.7 million followers, and has since revived his account as a friendly, not overshare-y, way to promote his new album, "Born and Raised."
About Simpson, Mayer told Playboy this: "Yeah, that girl is like crack cocaine to me ... Sexually it was crazy. That's all I'll say. It was like napalm, sexual napalm."
His musings on their 2006-2007 relationship didn't please her. In 2010, she told Oprah Winfrey, "I'm a little bit angry." When Winfrey asked why, Simpson replied, "Um ... well, I don't want people to know how I am in bed." Fair enough, right? But despite feeling "betrayed" and "disappointed" by her ex, Simpson said, "I'm just going to let that go."
Mayer dated the "Friday Night Lights" star on and off between 2007 and 2008. They officially broke it off in early 2008 and he quickly jumped into the arms of Jennifer Aniston. When asked about Mayer's rebound, Kelly told People, "I'm really happy – as long as they're happy, I am."
She quickly moved on with New York Yankees star Derek Jeter. They dated for three years.
Jennifer Love Hewitt
Mayer briefly dated Hewitt in 2002 and his hit song, "Your Body Is a Wonderland," is reportedly about the "Client List" star. Although their relationship lasted about as long as an episode of "Party of Five," it gave him enough material for a surprise comedy routine at the Laugh Factory in May 2006. Mayer dished during the stand-up that he never got to have sex with Hewitt because he was fighting off food poisoning brought on by bad fish. He later apologized to Hewitt, telling Us Weekly, "It really was me making fun of myself."