I recently put two new tutorials up in Google Docs - as always, feedback and any technical suggestions, etc. are greatly appreciated!
Working with Primary Keys and Generators - Quickstart with NHibernate (Part 4)
Working with Many to Many relationships in NHibernate
-Bob
Part 4: Interesting! we don't need to call the method ProductKey.Generate(NHibernate.Engine.ISessionImplementor session, object obj)