If you are in marketing, you've probably heard an adage about how many people an unsatisfied customer tell about his/her experience (hint: it's more than the number a happy customer will tell). Well, blogs seem to be a place where lots of people are willing to tell you all about their experience with their favorite product and the one they just hate. They'll tell you where they bought it, how they use it and what they like/dislike about it. Companies pay good money for that kind of customer research.
At Microsoft, I know that we have community folks that go into discussion groups and the like to get an understanding of how our customers feel about our products and out competitors products. But I'm not sure that this is someone's whole job. I wonder if such a person does or will exist. Will this change the scope of market research? Corporate blogging companies will be at an advantage because they understand the medium, but what about the companies that are not blogging? Will they realize that they have to enter the blogosphere where one disgruntled customer has the ability to tell 2 friends...are ten thousand; at least to engage that person that reviewed their product?
The blogosphere has a low entry barrier and the potential to shape opinions. Regardless of whether you are a corporate blogger, your company has to deal with the fact that bloggers can impact the perception of your product and/or brand. This doesn't mean that you have to blog, but you have to know who is blogging about you. And these people are potentially much more powerful than your marketing budget. Enter the blogosphere or suffer the (marketing) consequences.