Happy New Year John. Thanks for linking to the Roadmap.
I don't believe in complex measurement schemes -- for anything really 
To paraphrase Shel, marketers suck at math !
But I do think we need some baseline measurements for all mktg activity, including PR. Without measurements I think folks forget that our goal really IS to have an impact on sales. They get wrapped up in measurements and metrics that are meaningless.
The key is to agree on something meaningful but simple. You don't want to get so twisted into this that you spend more time measuring and justifying than you do communicating.
I think web site traffic is a great indicator and available at little costs to companies of all sizes. It's simple math (the only kind I do) -- if traffic goes UP UP UP after a PR launch, at least you know people are paying attention.
I agree that it doesn't measure the things that you mention. However, it does compare apples to apples in the matter of the investment in PR versus the investment in advertising.
Now to the biggie, what is the behavioral outcome of the target audience: did they buy, did they change their opinion, did they perform some action.
I think Katie made this clear in her post that this is just one more tool in the toolbox, not the end-all.
Susan and Kami:
Thanks for the comments ... you both add some excellent perspective to the conversation.
I'm not against measurement, but I think it's very difficult to directly tie a news release or even a communications program directly to the bottom line.
Sometimes, yes ... but more often than not, your communications effort is just one element in the giant soup mix of what causes behavior or changes perceptions.
For years, PR people have been chasing the Holy Grail of measurement. I don't think these values or ratios are the answer because they are too easy to shoot down.
Commenting by HaloScan
