Thanks Meter 203
Join Date: May 2010
Location: East Bay, Northern California
Been tweakin on mine pretty hard, so not everything is quit "Normal" at the moment. But try this, plug in your USB, hold down power + down volume, and keep holding them down. The phone should reboot and you should see the yellow digger.
And yes its ok to power down from this state, even though it says don't power down. Just never, ever, power down in the midst of an update, represented by a blue bar. Something you would be initiating on your own anyways.