Paid links are always controversial. I found it interesting that "direct link purchases from individual sites/webmasters" was considered by your panel to be the fifth most effective link building tactic yet "link acquisition from known link brokers/sellers" was the second highest negative ranking factor. Any thoughts on this? Does this reflect the fact that even though paid links in general have a bad reputation, they're still widely employed?
I think that's correct. Link buying and selling is still a very popular activity in the SEO sphere, and while the engines continue to fight against it, they're unlikely to ever weed out 100% of the sites and pages the employ this methodology. Link acquisition via this methodology is incredibly attractive to businesses and something the engines have also instilled as a behavior - with PPC ads, you spend more money and get more traffic. It's not unnatural that companies would feel they can apply the same principles to SEO.
While I think the engines still have a long way to go on this front, I also believe that, at least at SEOmoz, where our risk tolerance is so low, the smartest way to go is to play by the engines' rules. Why spend a few hundred or few thousand dollars renting links when you could invest that in your site's content, user interface, public relations, social media marketing, etc. and have a long-term return that the engines are far less likely to ever discount.
