I mistakenly complained in AdSense forum about retargeting and how annoying I was finding it. As some said that "it works" I wonder about how you actually measure the success of you (re)targeting campaigns. Can you see the conversion of retargeting actions only?
I think that if you run a campaign that is large enough to have a true impact on business, and if you have a good point of conversion on your site, a conversion pixel can be used to assess the success of a retargeting campaign. However, as retargeting gets more and more local, websites that don't convert online (attorneys, roofers, restaurants, car dealerships) will have to consider that display advertising acts a lot like television or radio or billboards (they are online billboards, after all) and will have to measure their effectiveness just as they do other creative advertising strategies - based on SALES!
[edited by: buckworks at 4:14 pm (utc) on May 1, 2014] [edit reason] Removed self-promotinal link [/edit]