Well I will state that I am jailbroken now on 4.1 and I remember when I went from 4.01 to 4.1, I had to kick out of recovery mode to do so
Maybe it is that I had that issue that I perceive it more but it does seem like it is more prevalent than it use to be (things going wrong that is)
With that said, if one uses TU to reset the hosts back to Apple, none of this error would happen right? I assume it is when people use the restore without unchecking the "hosts to cydia" box in TU
COuld very well be wrong though