My personal observations, and summary of information taken from a number of forums, and the personal observations of 20 or so webmasters with a combined traffic of 10s of millions of visits per day
I've tried (my best) to summarise what I've seen in relation to this, and not editoralise too much
Disclaimer to newer folk: Take this for what it is, a set of observations - somewhat muddied by our personal experience and expectations. We do not work for Google, we only have part of the picture. Summary
A fairly clear pattern has emerged: The fight against spam was HUGE. At some level Google failed to react to the crossfire generated, and collateral damage. It hit widely, but no one more than UGC (User Generated Content). In part made possible by the narrowed gathering of, and seeming reluctance to consider, wider-perspective webmaster feedback. Why all this UGC?
We are normally an order of magnitude bigger than everyone else. Things hit us first and more noticeably. Our area is 'gray', both quality and otherwise. We fight SPAM at the site level and tend to see updates before others do (due to our reach and size). In some regards, we may signal what's to come for SMEs (small and medium enterprises). UGC site owners are hurting (pretty much across the board).
Even StackOverflow seems to have been hit in 2013 (according to alexa*)
"Too many updates, they're being careless." - 500 a year according to Matt.
WebmasterWorld (alexa* again) declining since 2011 (it's safe, don't worry, we all love it here!)
Reported: Perhaps a general decline in search traffic via Google (now at #2 spot on Alexa - Facebook #1)
Quality doesn't seem to be much of a factor. Many authorities hit hard.
No clear examples (so far) of older UGC that survived.
Examples of things like 'blank' sites, double H1, '2005 black hat SEO' making it into the top 10 (a lot of this seems to be done at the bottom of the page) Read the thread, it's quite entertaining*
Bing showing very different results.
Panda provided a boost for a lot of us UGC. I saw my traffic rise through 2011-2012. (21.5 nov 12 corrected that.)
(Unsure) Custom software, or updating your look may have resulted in another inadvertant penalty (*cross-fire, sticking your neck out)
Non-UGC: Manual adjustments for keyphrases patching and semi-correcting the problem here and there.
"Hard to say where traffic drops are occuring, it's just 'everywhere'"
Links are at the centre of this storm. UGC Webmasters forced to No-Follow everything meant organic user preference from the wider audience was lost. Hurts everyone.
The google product forums have unintentionally become an abysmal way to keep us from getting answers. (Our experience as we ventured in there recently to hunt down some answers)
Brands may not be favoured, but at this level of chaos - they're more likely to survive it.
According to some people: Black hat has become non-viable. If that's true, it may have been done by over-reaching on too many signal patterns.
I've left a lot out (paid links), as I haven't personally been following it. This is just my own meandering personal perspective.
* "Cross-fire collateral damage." In a time when bullets are flying around you, keep your head down. In web terms, that would mean blending in with the crowd. "Use traditional software, don't do anything custom-made. No-Follow every link." That's not a great situation, that hurts everyone.
* Alexa works pretty well (in my experience) for large sites - those of us in the top 10,000
* Some entertainment: [webmasterworld.com...]
Fully personal opinion
I'm a white hat SEO, for 15 years. First website made in 1994. IMHO: Good content has never been hit so hard, and to this extent. Some may argue, the current state of affairs will result in the loss of smaller deserving businesses, those without the deep pockets to survive turmoil to this degree.
IMHO Focus on content, even now. Nothing else has a longer-term chance of survival.
I don't believe any of this is intentional on Google's part, I believe them when they say they don't favour brands. PPC would be a better place for brands in general (they are used to that and can afford it, everyone wins). Leave organic to a fair mix of SME and brand - then the ad space used above the SERPs would be acceptable.
Question to the community
Do we need, as a community, to establish better dialogue with Google? If so, a proper way to do that. To keep the signal to noise ratio down. Real Googlers participating, hundreds (not 2). I believe some inside the web-spam team might agree, please speak up.
[edited by: goodroi at 1:18 pm (utc) on Jun 12, 2013]
[edit reason] per author's request, added question to the community [/edit]