Asian Development Bank (ADB) makes pretty interesting use of RSS on its site. Contractors can use RSS feeds to get up-to-date, self-selected news of business opportunities.
Blogs are nothing but databases for dummies. Readers control what they read, when they read, according to date and category.
What I find interesting about ADB's use of this technology is that they haven't prettied the page up. With the familiar orange RSS signals on the right, ADB signals 'This is a blog!' That's such a good idea, because anyone who already reads blogs will get the message instantly. ADB is exploiting blog conventions in several ways. The payoff for ADB includes quick updating, version control, and a user-friendly interface.
We haven't even started on the potential of blogs for business. Marketing is the least of it.