Vista SP1 Update Locks Out Some Users

Windows Vista SP1, which began rolling out via Automatic Update, has left some users' machines unbootable. The update loops forever on "Configuring updates: Stage 3 of 3 — 0% complete. Do not turn off your computer." "Shutting down"... restart and loop. Echostorm notes having found traces of what sounds like the same bug in early beta releases of SP1. It's unclear how many users are affected. So far there is no word on a fix from Microsoft.