For what it's worth, the default root shell is now /bin/sh instead of csh. I think that's true as of 14.0. /bin/sh is also a better interactive shell than it used to be, though yeah, I don't use it to do anything other than install my preferred shell.
Right, but isn't the default non-root shell still tcsh? Zsh and ksh are both under BSD(-compatible) licenses, and it would be a huge usability upgrade if they could just set one of those as the default shell for everyone.