There are now 2 white papers published on the new AutoCAD 2006 feature Dynamic Blocks. These documents explain the feature, best practices, and tips and tricks to help get you started in using the powerful new feature. The information is from those requiring basic as well as advanced information. There is a part 3 to be published later and I will announce that one when available.
Part 1: Dynamic Block Overview and Quick-Start Tutorial
Part 2: Inventory of Block Editor, Commands, Parameters, Actions, and Parameter Sets
Link to Dynamic Block white paper series