You can use business rules in many ways. I think one of the most important areas is in customer segmentation. There is initial segmentation around which customers to target with which offering (e.g., cross-selling, multi-variate analysis). There is secondary segmentation around which message will compel them to act on an offering (e.g., campaign management). Additionally, there is segmentation around which channel they are likely to respond to (i.e., e-mail, text message, letter, call, web, TV, radio).
My 90-year old grandmother who does Masters swimming called earlier this week because she had a letter asking her to send in some information to them via e-mail. She can barely use a phone without silver dollar size numbers so asking her to respond using e-mail is ridiculous.
As you design processes that spawn communications or create messaging, thinking through the multiple levels of segmentation and the supporting rules is critical. Ideally, some type of "artificial intelligence" by which the rules are automatically updated as the system learns is ideal. Linking success (i.e., outcomes) to the logic used allows you to refine and improve your communications and marketing over time.
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