I’m no SEO expert (unlike a few of the affiliates out there who I’m sure could make a decent living on the SEO front alone), but it was interesting to hear the SEO discussion at CAP Euro back in January where there was a little disagreement amongst the panel.
The general argument went along the way that it’s quality rather than quantity of links that is now important in SERPS.
Maybe that’s why some established sites don’t appear to spend too much time on link exchanging?