Line56 on The Case for Blogging:
"In corporate blogs, the value of information is closely connected with interaction. Giving readers this kind of information creates an impression of trust and transparency; it doesn't matter that the information is ultimately being presented for the sake of marketing, it makes readers feel as if the company is sharing something with them, and it helps to build a community. This really kicks in at the level of reader comment, when readers talk back to the blogger.
This is where corporate bloggers are dropping the ball. The authors of personal blogs tend to reply to comments, and even tailor some of their own content in response to comments. This is the final step in making the blog a true online community, and actually co-opts readers as part of the blog itself, as they also create and inspire content.
Unfortunately, some executive bloggers are not closing the loop by getting involved in the comments sections of their blogs, where some genuinely interesting and answerable (that is, without legal implications) questions about their companies' products, strategies, and competitors are going asked and unanswered. This creates frustration."