I'm on F17 with updates-testing enabled. After updating last night, I'm seeing syslog messages like this: May 20 22:23:30 jik2 TIFIER=systemd-logind[795]: New session 46 of user gdm. May 20 22:23:30 jik2 TIFIER=systemd-logind[795]: Linked /tmp/.X11-unix/X0 to /run/user/gdm/X11-display. Previously they looked like this: May 17 09:48:29 jik2 systemd-logind[759]: New session 6417 of user gdm. May 17 09:48:29 jik2 systemd-logind[759]: Linked /tmp/.X11-unix/X0 to /run/user/gdm/X11-display. Note that "TIFIER=" at the beginning of the messages.
I see the bug in this commit: http://cgit.freedesktop.org/systemd/systemd/commit/?id=4cd9a9d9ecf3a8835e21930f3215a5f5b74144be (The length of the string "SYSLOG_IDENTIFIER=" is not 11.)
Fixed upstream: http://cgit.freedesktop.org/systemd/systemd/commit/?id=fca1b90a0dd2800f8ec9e31ff0b942312b0b8bb0
https://admin.fedoraproject.org/updates/FEDORA-2012-8127/systemd-44-11.fc17