econman - 6:56 pm on Oct 5, 2012 (gmt 0)
Why can't Google just ignore links it doesn't trust? Wouldn't that be enough...
Because Google doesn't have perfect knowledge -- it is only able to identify some of the "untrustworthy" links
Google has long been engaged in an intensive campaign to influence our perceptions and behavior. Things have recently escalated to the point where some are beginning to characterize this as a "war on SEO."
These sorts of warnings are perfectly logical when viewed in the context of a broad effort to discourage "building" links.
By increasing the fear factor, Google is reducing the perceived ROI of all efforts to "build" links, but especially any activity which arguably falls within the ever expanding scope of their warnings.
This, in turn, makes it harder for "blog networks" and other sites that sell links to make money or survive economically, and it discourages sites from buying links or spending money on SEO.
In turn, this encourages a broad shift of marketing dollars away from SEO and towards SEM/Adwords, and it discourages the proliferation of the sort of low-quality sites which Google is struggling to keep out of its SERPs.
While the propaganda battle is currently being targeted at "bad links" the same incentives will exist for Google to discourage any sort of SEO efforts that "manipulate" their SERP results, and to encourage site owners to focus their marketing efforts on Adwords, and to focus on "building a quality site" rather than marketing it through SEO.