econman - 6:39 pm on Feb 25, 2011 (gmt 0)
I don't see how all this commentary about how Google must have given a free pass to "big boys" can be reconciled with this comment on the official Google blog:
"If you take the top several dozen or so most-blocked domains from the Chrome extension, then this algorithmic change addresses 84% of them, which is strong independent confirmation of the user benefits."
If you take it at face value, that statement indicates that the new algorithm change is pushing all but 16% of the biggest "low quality" sites down the SERPs for the limited set of queries that are affected by this change.
Which leads me to a second point: the change is tightly focused on a limited group of queries.
...in the last day or so we launched a pretty big algorithmic improvement to our ranking—a change that noticeably impacts 11.8% of our queries—and we wanted to let people know what’s going on. This update is designed to reduce rankings for low-quality sites
Hence, the impact so far is going to be relatively small (good or bad) for most sites -- assuming the site has a reasonably diverse range of content, matching a wide range of different search queries.
However, this might be the beginning of a significant long term shift in the incentives we all face. To my knowledge this is the first time Google has explicitly said it is starting to be concerned with content or website "quality" (in the past it has always talked about "relevance" even in a context where most people would be thinking about quality).
Up to this point, Google's algorithms have created strong incentives for everyone to focus on quantity (of links and of content). The incentive has been to provide content that is the "most relevant" to the query (e.g. has a page title that exactly matches the specific query). There has been little or no incentive to provide quality (e.g. provide in-depth information, original research, solid, up-to-date facts, written in proper English).
This could be the start of something very good.