There's a discussion involving brand bias and the influences and behaviours of Adwords campaigns in conjunction with organic serps.
Does anyone have any experiences about the added performance efficiencies of running both in conjunction with each other. References to the Google research studies and a post by Robert Charlton are included here :
Excellent discussion - re-answered a question I've been curious about for years that is now cropping up get again with a bunch of new clients.
My original search query on this topic included the word "synergy" and it is interesting that this link points to excellent useful discussions and various other experts (Greg Jarboe / ICrossing) discussions that are all about "symbiosis" between organic and AdWords traffic.
I guess it pays to Google on synonyms!
Love to get eWhisper and various other AdWords WebmasterWorld admins and senior members in on this topic!
I've done a lot of talks at Pubcon over the years on this topic, and overall, I'm a big fan of doing both at the same time.
I often see CTR & CR go up when you are twice (or more with universal results) on the page. There is some cannibalization, but in most cases, the 'free' traffic you're now buying is worth the additional traffic you get from paid.
It use to be really easy to do these tests yourself; but its much harder now with (not provided) as you can't see traffic volume on keywords for organic anymore to test the difference between buying and not buying certain words. You can use destination URLs as a bit of a proxy to see the traffic difference to particular URLs with and without the paid traffic, but that proxy isn't 100% accurate.
However, overall, I see a benefit 90%+ of the time.