The IBM San Francisco project plays with similar
issues as we do:

http://www.ibm.com/Java/Sanfrancisco/

Some correspondences:
simple business rule == command == personality 
complex business rule == command == APPC == class graph view

-- Karl

Pricing and Discounts 
Provides the ability to establish and maintain both 
inbound and outbound pricing information. 
Order Management has the sophistication to establish both base prices 
and prices using limits. Its discount process has the 
flexibility to establish various types of discount structures for 
the various types of orders. Both pricing and discounts 
are associated with business rules and policies that designate 
the information to be used for a particular order situation. 

http://www.ibm.com/Java/Sanfrancisco/concepts/concepts.html

Intent
The business environment changes over time and the 
application supporting that environment needs to be able to 
react to those changes, while minimizing the impacts to the 
overall application. An additional need is to provide a way 
to update a group of objects at once while ensuring that if the 
complete group is not updated successfully, the changes are all reversed. 
The business logic may span many business objects (classes), 
which makes the placement of this logic within 
one particular object impractical. 

Concept
Commands (similar to the Command pattern in the Design Patterns book) 
are objects with the sole purpose to provide a separate 
location for a specific piece of business logic processing. 
By focusing this logic into a single object, the particular 
business logic changes can be modified without impacting various users, 
thereby isolating the users from the changes. 

Benefits
The implementation of business logic affecting several distinct 
business objects through Commands clearly brings advantages 
to maintenance and also allows application designers 
to isolate activities. By encapsulating the business logic in a 
Command object, using programs are isolated from 
changes in that piece of logic. It then becomes much easier to replace, 
modify, or enhance a certain piece of logic without impacting its users. 
Command objects also localize business tasks, 
making it easier to locate them. 
This approach increases the flexibility of the framework.