I ran across one of the most concise explanations making a marketing case for blogs on a software development blog from a company called Visionpace.
From a business perspective blogs are no different from marketing channels like video, print, audio or presentations. They all deliver results of varying kind. The kind you can expect from blogs is mainly about stronger relations with target groups important to you. Below are a few blogging advantages we hope to benefit from. . .
Read the rest from the Visionpace blog