That's not really doxing, I don't think. He's got links in his profile and the same username as on Twitter.

Lots of people know Randy. He's had posts on the front page of HN.

As much as a developer can be a "public figure", I think he is one.

If John Resig posted about DOM libraries and someone mentioned that he wrote jQuery, I don't think anyone would suggest he'd been doxed.