Measuring influencer reach and blog impressions is probably one of the most challenging aspects of entering a Web 2.0 strategy today. So, you created a social media campaign with outreach to influential bloggers. How do you measure the influence it had?

If you’re Paula Drum, VP of Digital Marketing at H&R Block, you’ve hired an agency to help monitor blog mentions. Drum’s team measured 6 million impressions of the company’s social media strategy in the blogosphere. That number includes mentions and people they think were reached by those mentions.

Those are good numbers but Paula says blog monitoring is still very imperfect at this point. All of the tools have plus and minuses. It’s still an emerging area of measurement.

Influencer reach is even harder to measure, she says. “Having someone like Robert Scoble, who is a very big influencer in the technology circles, talk about our brand in a positive way, we know it’s powerful,” says Paula. “It’s just really hard to measure the impact.”

The closest solution to this that I have found is in a white paper from an Edelman PR consultant’s blog Technobabble 2.0. If you know of other solutions, let’s talk. MarketingSherpa likes to be aware of measurable tactics that work.