In his blog, Annraí O'Toole discusses building for change. In particular he quotes Roy Schulte of Gartner
Roy suggested that in the past, most applications were "built to last" -- their longevity and robustness was the most prized features about the application.
However, nowadays, the most important thing about an application is that it is "built to change" -- its ability to reflect the dynamic nature of business is now its most important feature.
He goes on to say "We still need the application to be reliable and robust, it just needs to be easier to change" and that "Using services to enable rapid change is probably the most important trend for the next five years!".
I could not agree more. I won't repeat the reasons for thinking that business rules is a perfect technology to develop services that can be rapidly change - check out the rest of the blog.