My wife's Dell with Windows 10, 64 bit is another victim of the update, and is now a brick.
Her update was done automatically, and before I knew there was an issue I manually ran the update on my own machine, but tried to cancel it after Googling. Avast now wants to reboot, and I fear that my laptop will also fall victim to this unfortunate upgrade.
Seeing as the issue surfaced on February 7th across many devices and configurations, I think it would have been wise to have paused automatic updates until the issue/s had been resolved.