I've run my main site without using ads since inception... and in the last couple of weeks I have now added Adsense ads. My site growth has been steady, stable and consistent from a statistical view. Added Adsense two weeks ago, this week my traffic jumped around 200 per day. Just so happens advertisers are targeting my site specifically with their ads. Coincidence??? Or not??? Like seriously... is Google actually biased and gives a little more to sites running their ads? I know they tend to punish those using affiliate links, have for years... but this is just ridiculous of Google IMHO. They're supposed to be unbiased in traffic and rankings, yet there are known partners who get precedence for rankings, and now this noticeable traffic increase since adding Adsense.