The etc-update howto says that etc-update is deprecated (http://gentoo-wiki.com/HOWTO_etc-update), but according to the person who dealt with my bug report on emerge and etc-update (http://bugs.gentoo.org/show_bug.cgi?id=130128) it isn't. Assuming he's right, the howto needs correcting.
We don't maintain or review Gentoo Wiki for correctness.