I'd wager that more nerds run Linux on the desktop (or laptop) now than they did back when Slashdot was getting started. The biggest loser of developer mindshare in the years since has been Windows.

But, no one (in their right mind) is using Mac OS on the server, and any developer with a successful website has a lot more servers than they have laptops or desktops, so I reckon they're more of a "Linux user" than a "Mac user".