I get loads of emails around BRL licensing.
Take a look at this doc. It provides a comprehensive overview of Microsoft Dynamics licensing
Document includes an overview of basic licensing concepts and how they are applied, licensing guidelines/rules partners need to be aware of when making a quote/placing an order, and descriptions of the various licensing options available and when to use them. The guide also covers licensing programs, licenses for partner use, and Volume Licensing SKUs on the Microsoft Dynamics price lists.
Its not available on partner source yet. Drop me an email if you would like a copy.
Once its on Partner Source i will blog the link.