indyank - 3:22 pm on Feb 26, 2011 (gmt 0) [edited by: indyank at 3:39 pm (utc) on Feb 26, 2011]
it is likely that the changes that have just been rolled out have been verified and improved through a few months of low-profile multi-variate testing going on in the background
google had been doing a lot of tests/changes recently and one site that got hit by this update never faced any issues in all those tests.This site saw an increase in traffic with every update they did so far and had the best traffic on Monday, Tuesday and Wednesday.When this roll out was finally announced, many pages (but not all) that pulled traffic got pushed down to page 2 or 3 for their primary keywords.
is this data primarily at the site-wide level, or at the page-specific level
It does look sitewide (refer above) and it does appear some generic factors were used to filter its pages.Most pages now appear in page 2, 3 and 4.
The other competing pages on the front page are thin pages supported with lots of auto generated internal pages.These are sites run by content producing business houses like eHow (adsense premium publishers).All of them remain intact.
What is unique is the site never got impacted until now.It is like google simply pulled up those sites that weren't run by their premium publishers and pushed all their traffic pulling pages down by a few pages in SERPS.
From a quality perspective, I would rate this site as very good and it is neither a thin site nor does it contain duplicate content.Content is unique and based on research.
But yes, partial feeds are being syndicated ( title and a brief description) and these do appear on several feed aggregators.
Another interesting thing that happens now is the site is the site pulls traffic higher than usual from other parts of the globe and the pages that were pushed down in US SERPS are ranking highr than earlier in other google TLDs now.
US traffic is way down but compensated to some extent elsewhere and the overall traffic drop is 10-13%
For those who focus on PR, the site has a toolbar PR 6 to home page.Pages that went down has PR 5, 4 and so on.
Backlinks are natural and like Donna said, there are some funky sites linking to those pages and domain naturally.But there are no high profile paid/discount links or links from large groups (farms) of sites that we often see in sites run by business houses.
[edited by: indyank at 3:39 pm (utc) on Feb 26, 2011]