Found some great MSDN articles for those embarking on on Workflow adventures within MOSS (Sharepoint 2007)
Microsoft Windows SharePoint Services 3.0 provides a robust, customizable work environment for users to create, collaborate, and store valuable business information. Windows SharePoint Services now enables you to attach custom business processes to these documents or list items.
Custom business processes are represented by workflows. A workflow is a natural way to organize and run a set of work units, or activities, to form an executable file representation of a work process.
This process can control almost any aspect of an item in Windows SharePoint Services, including the life cycle of that item. The workflow is flexible enough to model both the system functions and human actions necessary for the workflow to complete.
And, there’s another player in this arena : Nintex Workflow 2007. Have just returned from an overview & demo at MOSSIG. More soon.