There seems to be one pattern that jumped out to me based on all the replies here and on the Oct thread:
Low quality equates to low traffic.
People are saying 50-90% loss in traffic. When that number translates into hard number such as 500 or 100 uniques only. To me, if you had an exact match domain and you're only getting that much traffic, clearly the domain name is carrying you, not content.
Has any site that isn't a micro affiliate niche site been hit?