This is anecdotal, but I noticed a 25% drop in traffic ever since I added adsense to my web application a few days ago. Prior to that, traffic was gradually increasing.
However, If you put too many adsense units at the top of your page, Google would penalize you for a bad user experience. Maybe you could test with different combinations and see whether rankings change.
I assume the drop was in search referral traffic - did specific keywords get hit more so than others? If you're whole site has been penalized, you should see the affect across all your keywords. Also check out webmaster tools for more insight - https://www.google.com/webmasters/tools/home?hl=en
[+] [-] domaniac|12 years ago|reply
However, If you put too many adsense units at the top of your page, Google would penalize you for a bad user experience. Maybe you could test with different combinations and see whether rankings change.
[+] [-] kitcar|12 years ago|reply
[+] [-] thejteam|12 years ago|reply
If(Page contains Adsense or any general ad server) Then drop off front page.
Instant increase in search quality results. Eventually taking market share from Google.
[+] [-] leephillips|12 years ago|reply
https://news.ycombinator.com/item?id=6423171
[+] [-] cantbecool|12 years ago|reply