Comment 19 for bug 1043518

plymouth seems a bit suspect here for a couple of reason
Virtually all users reporting or confirming this, here or elsewhere, had this start occurring with live images shortly after 08/16
(I have a 08/15 image here that works fine, plymouth_0.8.4-0ubuntu1
Plymouth got a major upgrade on 08/16

Additionally there is a way on this hardware to now cause a corrupted unity greeter on an install, with the default plymouth packages downgraded to 0.8.4-0ubuntu1 it doesn't occur.
(a bit involved & requires 2 12.10 installs