I updated to x11-base/xorg-server-1.16.1, and the ebuild printed the following: You should consider reading upgrade guide for this release: http://www.gentoo.org/proj/en/desktop/x/x11/xorg-server-1.16-upgrade-guide.xml However, that URL gives me a 404.
PS: Also, the grammar is wrong in the message. It should be "reading the upgrade guide".
*** This bug has been marked as a duplicate of bug 517408 ***