I've just updated lvm2 in F19, the new package is in testing repository now.
The main problem was in missing scan for LVM metadata on MD devices at right time. This missed scan caused the MD device to be ignored by LVM autoactivation hook. Hence the LVM volume was not activated and the mount point not found as a consequence, causing a timeout for the mount point. For more information about the problem, please see https://bugzilla.redhat.com/show_bug.cgi?id=957692#c20.
Anyway, the problem should be resolved now. Thanks for reporting this issue. If the problem still persists even with that update, please, add comments to the bugzilla report mentioned above.