Priscilla Chan has always taken her relationship with Mark Zuckerberg seriously; she famously sealed a contract of dating rules before moving to be near him in California. But the medical school student just got more serious than ever before, listing Zuckerberg as her "partner" on Facebook - and adopting Zuck's mother as her own.

A screenshot of Chan's Facebook profile, which was either a private version or which has since been altered, was snapped by BetaBeat (see above). In addition to revealing that she's tracking ousted Facebook president and notorious playboy Sean Parker, and that she's a John Mayer fan, the profile also shows, under "recent activity," that Chan has been on a recent tear updating her relationship information. In addition to listing Zuckerberg as a partner and his mom as her mom - meaning Zuck is technically dating his sister, YUCK - she lists Zuck sis Arielle Zuckerberg as "unknown." That's actually quite an apt way of describing how Silicon Valley looks at people who, like Arielle, fail to get venture funding.

Reverse adopting your boyfriend's mom would be a very, very bold step if you hadn't reached some sort of mutual understanding about your future together. Presumably, Zuck and Chan have done just that. And you can't blame the girlfriend - err, make that "partner" - of one of the world's most notorious backtrackers for, once again, locking down that commitment in writing.