The part that is missing, that would enable more focussed discussion, is
where the DaniWeb (or other sites affected) changes (gone, dropped, same, up) occurred. Most Panda affected sites did not lose all their G traffic. Dani mentions that she (in the initial hit) lost ~40%. So, which pages? for which terms? etc. That is the sort of analysis that may highlight the algo shadow of what is now targeted.
Of course that requires both a benchmark and a history for pages and terms. Not sure how many sites track that. And few if any are likely to share

Given that DaniWeb had managed to recover (plus some) to beginning of year traffic volume by doing quite a drastic makeover this latest drop is actually quite intriguing. Is it a matter of kind (added, new input) or degree (existing input being cranked up/down)?
Knocking my head against desk... so far my sites seem boringly status quo with regards to Google traffic. Long may it remain so.
Note: there are rhythms to the traffic in volume and quality that are disconcertingly regular but that is a whole other conspiracy theory.