tedster - 9:34 pm on Mar 29, 2012 (gmt 0)
A big reason why this idea of negative SEO has gained so much traction in recent times is the absolute FLOOD of messages about unnatural backlinks sent out through Webmaster Tools. That's where Google's big error is, IMO - in those indiscriminate, automated messages.
I seldom see a link profile that doesn't have that kind of spammy junk, and in at least some cases I know that the website itself did not have anything to do with placing those spam links. In other cases, after a little poking and prodding, I do find that in fact they DID have responsibility, but never thought much about it because there were no immediate repercussions, so they forgot all about it. (Oh yes, one of our workers did run xrumer a few times, but nothing recently.)
My feeling right now is that Google sent out that barrage of messages without much forethought, and indeed, may have sent them to any webmaster whose profile shows bad links beyond a certain level - without much thought given to how legitimate the criticism is in each case.
In some cases, it seems like ignoring the message has so far caused no problem. In other cases, rankings did take a dive within a week to ten days.
The biggest problem for me is that Webmaster Tools data has been notoriously undependable. That makes it very difficult for me to buy into these warnings.
Does negative SEO exist? In some markets, yes... it's like a gang war! And that's nothing new at all. The funny thing about those markets is that the businesses involved also use all kinds of black hat ranking tactics anyway.
If these recent messages from Google are an attempt to clean up the "sewer" that Eric Schmidt complained about, they are a dud and a public relations nightmare.