According to this Business Week article you best get blogging asap, because you can bet that all your competitors are doing it.
This is really a hot discussion right now amongst business owners: to blog or not to blog. Seems to be a boon for some and a bust for others. For me, as a free, fun, and easy way to get the word out about my company and all my silly ideas, it's more of a "why not!?" question.