Same here.
I'm actually the person in charge of our security, and, as we take security quite serious, the auto-update is set hourly (which is btw the default). McAfee let the faulty DAT 4 hours (!) online, ...
I got it offline about 20 minutes after the first machine "hit the ground", but by then 95% of my machines had the update (550 machines over the whole of our country).
With the IT team we figured out a solution about 2 hours after it hit, even before McAfee came with a solution (which, at that time, wasn't even working...) and we had everything cleared up in 7 hours time, but i can tell you, those were hell...
Luckily, the whole it team is on Windows 7, for testing purposes, so we were able to continue to work and coordinate the "rescue mission".
I don't even want to imagine what the damage would have been if it also affected 2008 machines, which meant all our servers...