The word from on-high is -- don't keep trying to update this thing; We'll e-mail you when the fix is ready. It puts my mind to work on other things. Frankly, my ATV2 ver. 4.2.1 does all it needs to. However, I don't like the mystery behind this particular Servergate. I was briefly taken aback when my phone counselor from Apple seemed to scoff at the wee enhancements I was missing as a result of not being able to update this device. But she did also apologize effusively.
And yet - considering that some have received this update - one has to wonder what's actually going on.
It's all Big Brother. Better get used to it.