Mr. Taylor (Photo: Google+)

Looks like we're gonna have to add another name to our Facebook Mafia list. Chief technology officer Bret Taylor told Kara Swisher at AllThingsD that he will be leaving the company for an "undetermined startup." Shortly after, he acknowledged his departure on his Facebook page. (A parting traffic gift, perhaps?) 

"I'm excited to be starting a company with my friend Kevin Gibbs," Mr. Taylor wrote, thanking Mark Zuckerberg as a mentor and friend.

Considering that Mr. Taylor has been in charge of Facebook's mobile and platform initiatives, this doesn't look good for the social network, which is currently embroiled in an SEC investigation and facing fresh scrutiny today about how a shift to mobile could affect revenue.

Get in line, SEC! That's the $100 billion question.