There’s more talk about the death of page views, this time from the Chief of Insights at Yahoo, the recently dethroned page view king.

The reason page views persist is that they are a key variable in the still dominant currency of online advertising — impressions, and its derivative CPM. Impressions themselves are merely the clunky online analogue to TV ad “exposure” — the currency in big money advertising has long been whether the ad was seen.

The reason Google has been so disruptive is that they abandoned not only page views and impressions but also all audience demographics, and they replaced them with the elegant keyword and click. Clicks have their problems, of course — they can be gamed and they are only a way-point on the way to a destination. But they sure beat the hell out of impressions as a clear measure of advertising value. CPA, or cost per action, has long been positioned as the next evolution, because advertisers only pay for the end result — the problem is that in many instances it’s difficult to attribute an end result, particularly long sales cycle purchases, to one specific ad.

I’ve written before that the future of online advertising lies in the fuzzy middle between direct response and branding — at the end of the day, the challenge is finding currencies for advertising that map to advertiser objectives.

It’s no coincidence that Jason Calacanis is studying multivariate analyses of advertising effectiveness — the “traffic game” remains a clash of titans (as Richard MacManus demonstrated), but all the action going forward will be the quest for Google-like innovations in advertising value.