Online publishers get short-changed for delivering impressions to brands that can impact people's perceptions and purchase behavior, but do not result in an action. Advertisers get short-changed if publishers deliver impressions that don't impact brand perception or purchase decision making, which, in a world of LIMITLESS impressions, will be more often the case than not.
I think there's a balance between the two arguments that will allow advertisers and publishers to exchange value fairly. I think that balance comes from looking at the value of impressions as an output, rather than an input. If advertisers paid for engagement, it would be easier to factor in the value of impressions based on the rate of engagement. For example: If Web site A delivered an engagement or click-on rate for 1% of impressions, and Web site B delivered an engagement on 2% of impressions, given the same creative execution on both sites (this is very important), then Web site B is delivering higher value impressions.
If a market existed where advertisers could see this, they should be willing to pay more for engagements on Web site B. Why? Because the advertiser can assume that those impression are attracting a greater share of attention (or the audience is a better fit for their offering). In effect, the value of the publishers' impressions will be priced into the rate they can charge per engagement/click. (For more on my definition of engage, read "I'm Sold On Engagement.")
It's still very possible, though, that in the short run, publishers will not get full value for impressions -- because advertising creative does not get people to click/engage, while still delivering value to the advertiser -- but this is less of a problem than one might think. Especially when you consider that falling CPM prices across the industry are probably already hurting online publishers, even those that could deliver quality consumer attention to advertisers. The key would be for publishers to innovate on the delivery of quality attention to advertiser messages, while an ad unit that makes sense for consumers in an online experience would be created. Add to this the idea that engagements add more value than simply "message delivery" -- which is all impressions can do, be they online or on television -- and advertisers and agencies will be motivated to create advertising that induces engagement, so that they can drive conversations with consumers and social media pass-along (more impressions, but this time peer-to-peer impressions).
This is by no means a solution, but a potential step in the right direction. Publisher who can say they drive higher engagement rates should get higher CPMs, and advertisers who get more people to engage with and share their content as a percentage of the impressions they received in a campaign will likely make a bigger impact on sales and branding objectives. For now, it seems that since there isn't a standard, there's a lot of opportunity for publishers and advertisers who are ahead of the curve on setting objectives that matter for major impact in the online and social media world.
Thoughts? Feelings? Then drop me a line below and watch as the conversation plays out on Twitter: http://twitter.com/joemarchese