We've been using impressions and clicks for quite a while now. In the beginning, we weren't sure what to exchange in the media market place. Ratings, share, reach, frequency, households, demos, and impressions - all of these served, and still serve, as currency in the media business.
But these had all developed over years and years of trial and error, competition, use, and finally, plain resignation to the dominant paradigm. The Internet was new, and though it looked a little like print and a little like broadcast, it was clear that the Internet was neither of these things.
Yet, in order to move the medium into the industry's field of vision, there had to be a way to talk about it that was analogous to what was already known and understood. There had to be a way to, first, quantify the medium so that it could be bought, sold, and monitored like other media. Then something "one step beyond" had to be attached so that the Web was seen as a medium like no other - a "killer app" that would allow it to be distinguished from the rest of the media pack.
The 'hit' was quickly seen as a terribly inadequate device for accomplishing the aforementioned, and is now a sign of someone who is either new to or does not understand the Internet when used. You better be a Kasey Kassem or a Sammy Sosa if you talk about hits these days.
Today, impressions and clicks are the most common ad units bought and sold in the online market place.
But maybe it is time that we take a look at something else to serve as the currency of exchange in the online media marketplace. Impressions are still the most common, but are terribly inaccurate. There is still debate as to how to count them, whether or not they are what we are told they are, and there are certainly questions as to how valuable the impression is.
I posit that content publishers begin to look at "audience" as the saleable commodity in the online advertising space. In print, a planner would evaluate a magazine, among many other qualitative and quantitative factors, by how efficiently it reaches the target audience. With websites, we can do the same thing, but I don't purchase an audience. Instead I buy a given number of potential ad exposures. If a site can sell me an audience against a rate base, like print can, CPMs can be brought into line with other media, but the out-of-pocket increases, making advertising the viable revenue model it should be for desirable, quality content.
For advertisers it means a certain guarantee of delivery against a target audience. Now, if I buy a million impressions on a site, I could be getting the same 100,000 people 10 times, or 1,000,000 people one time. With print, I've at least got a guaranteed potential for an "opportunity to see." That is, if a print publication's circulation is a million, there is the potential for a million individuals to see my ad. I don't have that on the web. Granted, this is a function of the way the medium