Two things surprise me in this discussion: the notable absences of (1) Google and (2) anyone whose traffic and ranking actually increased.
It's OK to start this thread to hear feedback, but given how strong the reactions are, I think the initiator could take the time to explain the situation and things to come a little (apologies if you did, I didn't read all 700 messages in detail).
And why does everyone seem to have lost traffic? I the algorithm was meant to rearange search engine results, surely some people should be seeing increased traffic? Or are the new results so irrelevant that no one is actually clicking? I doubt that. (again apologies if someone posted on this).