Tom is dead on - we recently began to do this ourselves, letting one employee devote half a day (at least!) to monitoring forums and relevant articles to our company for digital outreach efforts.

We're using OSE's Just-Discovered beta, Chartbeat, and SEOMoz's Fresh Web Explorer to track where the conversations are taking place. We've only been doing this for a week or so, and are using some utm_parameters to track traffic from the efforts. We're hoping to see some solid engagement and, for a bonus, create some online evangelists.