pageoneresults - 5:43 pm on Oct 27, 2011 (gmt 0)
I strongly believe that 3 Adsense ads, no matter how placed, will not affect your sites rankings.
I strongly believe otherwise. I've seen the effect of poorly placed ad units, it's called the back button effect which in turn contributes to high bounce rates which in turn affects your overall rankings not to mention quality scores.
How many times have you landed on a site that had 3 ad units above the fold and immediately used your back button? What type of signal does that send back to Google?
Of course there are always exceptions.
To me, any ads in my face that are placed in areas where I'm expecting to see content immediately leaves a bad first impression. In most instances, I'm using my back button and going somewhere else.
The AdSense Team's recommendations are not meant for everyone.