Yet: there's an inherent tension. Unless there's a credible threat people will go to another engine for natural results, for Google to degrade their own natural results slightly can improve Google's quarterly revenues!
Let's say Google is A/B testing a ranking tweak. Option A results in more searches (because people don't find exactly what they're looking for on the first try), and more clicks on ads (because they look relatively better). Option B results in one click on a natural result and nothing further.
Are we sure they'll always choose option B?
Maybe Google can add a new advanced operator: [-src:googlesyndication.com]. That is, don't return results that 'source' (as in <SCRIPT SRC="">) Google ad units.
Let's say Google is A/B testing a ranking tweak. Option A results in more searches (because people don't find exactly what they're looking for on the first try), and more clicks on ads (because they look relatively better). Option B results in one click on a natural result and nothing further.
Are we sure they'll always choose option B?
Maybe Google can add a new advanced operator: [-src:googlesyndication.com]. That is, don't return results that 'source' (as in <SCRIPT SRC="">) Google ad units.
I won't hold my breath.