Kevin's leaving Facebook marks three known defections from the social networking giant since the talent buy was announced, including Gary Burd's October 2009 exit and Ben Darnell, who joined Brizzly a month following.
Kevin did not indicate any specific incident as a contribution to his leaving, calling his work with Facebook's "world-class designers, PMs and engineers" a privilege. He says instead that it's "time for the next adventure", hinting he will take vacation and go into private practice.
He said as much to me earlier this week, saying, "I'm really excited to do my own thing after a summer vacation. No jumping from one ship to another."
Previous to Facebook and FriendFeed, Kevin led the design of GMail 1.0, Google Calendar 1.0 and Google Reader 2.0, after he had also spent time at Yahoo! at the end of the Web 1.0 era.