Here are the topics:
- Plug-ins: the organization of code into plug-ins; that are wired up using the Platform object.
- IAdatable: a neat trick allowing code to be added to an Object at runtime
- Workbench Selection: the workbench tracks the current selection; allowing you to listen to what the user is up to in one handy spot
Documentation harmed in the making of this post:
* IAdaptable (uDig Developers Guide)