/run has been widely adopted, but the /usr merge is a bit more controversial. I expect this will become another factor in the growing bifurcation of Linux into Red Hat-style distros and Ubuntu-style distros (see also systemd vs. upstart, Wayland vs. Mir, etc.) with a few "traditionalist" distributions like Slackware on the sidelines. As a Debian user, I expect that the next few years will be...interesting.