Now that Google has turned marketing into a quantifiable, profitable activity with measurable ROI, how is it that business blogging gets away with the same soft arguments that boosters of brand advertising typically use (and for which they have rightly been taken to task)?

The blogosphere is abuzz because Werner Vogels, CTO of Amazon, apparently mopped up the floor with naked conversationalists Robert Scoble and Shel Israel for not being able to quantify the ROI of corporate blogging.

Was Werner rude to Scobel and Shel? WHO CARES! If you’re writing a gossip column, then go to town. I’m interested in the business issue here.

Scoble attempts a response to the question about quanitifiable ROI, but without much success:

I totally forgot to mention that big companies like Boeing (Randy’s journal is a blog done by an executive there) , General Motors (Bob Lutz, an exec at GM has a blog), and Wells Fargo (which recently started blogging on its history) are seeing enough of a reason to start a blog (and continue doing them, even after the first year). The teams at Boeing and GM say they are pleased with the response and effect of their blogging and plan to continue doing them.

But, if you don’t like this approach, just visit Tom Moertel’s blog where he talks about his favorite coffee shop in Pittsburgh, PA, USA. When I visited that shop myself the owner raved about what blogging had done for his business. It turned his little coffee shop into one with an international presence. Thanks to search engines like A9, Google, Yahoo, and MSN. Oh, and he said he never got written up in the press before blogging, but now that’s a regular happening.

See, maybe that’s why I wasn’t able to defend blogging from a numbers point of view. To me this is a people business. One where raw numbers don’t matter. One where getting eight guys together in a Swiss Chalet can turn into tens of thousands of users literally overnight with doing nothing more than one post.

How, in a post-AdWords, can Scoble refuse to “defend blogging from a numbers point of view” and instead say it’s a “people business”? That’s hardly the approach that made Google into an advertising powerhouse.

And let’s be clear about something else: Case studies about small business success with blogging DO NOT mean there is (yet) a compelling dollars and cents case for blogging by big corporations.

Now you can argue that corporate blogging makes intuitive sense just like brand building makes intuitive sense. But, rudely stated or not, big corporations have every reason to question whether the risks of blogging (which Howard Rice outlines well — via Nick Carr) outweigh the potential rewards.