I can't find anything on this, but my traffic halved on Sep 1st. I did get an email from some SEO company I'm subscribed to mentioning helping you overcome the Sep algorithm change, but that's it. Turns out one of my keywords (the one I was getting a 47% CTR from) dropped from #2 to #24, and is now outranked by a page of mine on another site that I DELETED and put in a 301 redirect in March that points to the dropped page. Have just removed the redirect and replaced it with a page that says "This content is moved, click here to see it" as I suspect I'm getting a massive penalty because google thinks I still have two (completely identical, down to the byte) copies of the same page out there, at two different domains. How else would it be ranking a page that doesn't even exist over the destination that that page actually points to? Both the sites have equal pagerank, the destination of the 301 has a LOT more backlinks than the one that I redirected. Since I put in the redirect, the original site has continued to rank for some of the redirected content, has had a steady traffic increase, and the target of the redirect has constantly got up to about 15-20k visitors a day and then dropped back overnight to 7-10k visitors a day at every algorithm change - this is just the first time I've had a traffic halving and not been able to find anything about it. Beginning to really piss me off that I can't seem to get this site past 20k visitors a day, and the only keyword I managed to get ranking higher than #8 just dropped off the radar overnight, leaving every other keyword sitting at the bottom of page 1 where noone clicks on it. The site I redirected is 6 years older than the one I redirected it to (2003 vs 2009).