Domain object oriented packing vs. tier oriented packing
The newest sample, PetCare, for the 3.0 version, comes with a new packing method: domain object oriented instead of the tier oriented packing as what we have seen before. I can see the motivation behind this approach: modularization so that an application may take advantage of OSGI in the future.
I am wondering how to use this approach properly for an interconnected system. Take an online shop for example, the business domain objects: category, shop, product, order, order item etc. have a tight connection. What are the rules of laying out packings? Is it based on what repositories will be involved on the service tier?