Paul Argenti, professor at the Tuck School of Business Research, co-founder and chief advisor for Communications Consulting Worldwide (Fleishman's research and measurement consulting arm) and leading measurement thinker, was commissioned by Factiva to publish a white paper entitled Best Practices in Media Measurement
It's an interesting read. Though it's very well written, presents a compelling case and, rightly, places PR measurement in a broader business measurement imperative and context, the main thesis of the paper is by no means radical or new: that "establishing causation" between communications efforts and tangible business outgrowths is critical. The paper presents establishing causation as the future of communications measurement. I'd argue that we're already there and that we have been for years. Those in the communications industry would be hard pressed to have missed umpteen articles in various trade pubs, conference speeches, workshops and webinars pointing to marketing mix modelling used at Miller Brewing and Proctor and Gamble, among others, I'm sure. Though leading academics like Don Stacks would be, perhaps rightly, skeptical, the advances in technology and statistical methods (in one form or another) that Argenti refers to in the paper have been around, as Mark Weiner points out, for some time.
That said, the idea that technology is both making this type of measurement easier and more imperative does have merit.