I haven't figured out exactly what happened but some update from the last day or to broke booting on at least one of my machines.
The issue is that the file system type isn't being detected when getting ready to switch the root fs.
The work around is to add the rootfstype=ext3 kernel boot parameter.
Looking over the list of suspects, I am looking at udev being the culprit but don't have time right now to do the downgrade and reboots right this minute.
It isn't the kernel or dracut (at least directly) as trying to boot using older kernels and initramfs images that used to work, stopped working.
Sometime over the weekend, I should get a chance to narrow things down assuming I can reproduce it at home.