Companies that blog for marketing purposes fret about ROI: so we blog, how do we link to sales? Same with companies or other organisations who engage as part of their online advocacy efforts: OK it’s another medium, and we see how it’s different, but are we getting to legislators and other people who matter?
Sure, as a marketer you can connect your blog directly to sales channels (although I’d usually steer clear of this) while if you’re a campaigner, having a Google Analytics setup will allow tracking of domains such as the European Commission or Parliament, meaning you know exactly how much traffic you get from either. You won’t know if you’re reaching the most relevant people (you might just be preaching to the converted) but it’s a start nonetheless.
However, the measurements aren’t scientific by any stretch, so both groups often look at quantity and quality of comments as a measure of success, the logic being (rightly) that if people are reading but then also engaging in a constructive manner, the material you’re showcasing is having an effect.
However, to organisations who are producing top-tier content and getting loads of traffic but no comments, don’t worry about it too much: it’s presumably down to your target audience. Although we’re always hearing that unexpected demographics are going web-crazy, the fact remains that certain people might read blogs but will never comment, simply because they are still a little unsure of the medium. And if you work in truly traditional industries (say textiles, heavy machinery and chemicals) chances are that the people interested in your material are not the most avid web users, at least on average.
If I compare blogs I’ve worked on for clients, I can assure you that excellent blogs that are getting obscene amounts of traffic can get as little as one to five comments per month, despite plenty of efforts on our side to encourage commenting e.g. via questions or provocative remarks in posts. At the same time, blogs where the content is less interesting and the traffic less impressive are kick-starting week-long conversations via comments. Trust me, it’s not a reflection of the blog itself, but of your readership.
So what’s the best measure of success? I think it’s the “time spent on site” metric. Blogging is an element of content marketing i.e. the concept of guiding consumer action or shifting consumer perceptions via top-tier content which they buy into. Surely the ability to keep people on your site for a long time is the best testimony to this?
Steffen Moller 
Hi, Steffen
I agree with what you’re saying about comments not being the most important indicator of success. I’m sure, though, that there must be things a blogger can do to encourage people to comment. There must be a wealth of literature in real world public speaking or community building that could be applied to the internet.
And once people have commented once, it’s easier to get them to comment again! 🙂
A blog can be used for marketing purposes and even as a supplement to the company’s more traditional website. However I feel the nature of a blog is to engage the visitors — i.e. via comments, downloading, viewing videos, etc. So if the massive traffic is ‘simply’ viewing and purchasing products then why use a blog format? People can twitter about and refer regular sites to friends. Blogs extend your market reach into a different maybe more internet savvy audience — interaction is a solid measure of the effectiveness of the ‘blogging’ aspect — using current information, building up trust, expertise and caring around the brand.