This was a new one on me so I thought I would share it with you.
UCONN's Dr. Gil Dyrli does a great job of explainaing the issue. A blog attracts comments (well...not mine, but you get the point.) These comments can include links to products that are related to it, or not. Some fake sites are poser blogs. Which are really advertisers in blog clothing.
If this bugs you...<Fight Splog Now!