[adriand]

Why can't Google just apply a different algorithm to link farms that have appeared recently? Presumably anything relatively recent is either someone who doesn't know about the changes to the algorithm that penalize link farms, or is engaging in negative SEO.

[lifeisstillgood]

That's so obvious now you mention it :-) Any spammy link created now should simply be discarded, it either is an attack or it is a fool. Either way ignore

[rfergie]

That means that, as a site owner, I would be free to engage in spam SEO.

If it works, then I get rankings and traffic.

If it doesn't then there is no harm to me and I can go try some new tactic

[lifeisstillgood]

I don't think so...

1. I already have spam links pointing to my site. It hurts me so I clean up the spam and make the world a little better.

2. I add spam links to my competitor who previous had no spammy links. Google notices the dates on the links and does not alter the PageRank of my competitor. The world is not made a little bit worse. I stop doing it.

So as long as there is some clear cut of date for spammy links (and hopefully some definition) then it seems workable. Any black hat SEO will know no to bother adding post-Penguin/panda links - for good or ill.

[cosmie]

Exactly! Which is the exact scenario the recent update attempted to address: getting rid of the no harm aspect.

[jacquesm]

Yes, exactly. With the cut-off date being the panda roll-out.