Sgt_Kickaxe - 1:20 am on Feb 12, 2012 (gmt 0)

Warning: if you replace ads such as adsense with links to affiliate offers your pages will become considered affiliate in nature and too many of those on a site will cost you traffic SITEWIDE (not just on the pages with the ads).

I don't know what the thresholds are for number of affiliate offers or number of pages with even one offer but when you cross it your site will take a sitewide traffic loss, to all pages. Just an fyi - I've both seen this on other sites and tested it on my sites.