My latest article on programming Publisher, Using Tags to Store Custom Information in Publisher 2003 and Publisher 2002, has just been published on MSDN. As the name states, the article talks about using the Tags collection of the Document, Page, and Shape objects in Publisher to store information, such as custom variables or state information not normally persisted in a Publisher file. You can use the Tags collection to persist a wide range of custom information within your publication, at the publication, page, or shape level. An interesting aspect of the Tags collection is one of the rare pieces of the Publisher object model that doesn't have a counterpart in the application's user interface.
If you've been reading my Publisher blog entries, you got a preview of the information in the article here, here, and here. But this article builds on that material and is worth a look even if you've read those entries.
I'm pretty happy with how this one turned out, especially the in-depth examples using catalog merge. I knew that when you perform a catalog merge, all the shapes in the catalog merge area are copied for each record. What I found out was, this includes any tags you've assigned to those shapes. Which lets you do some very interesting things, like embedding merge data source information within the shapes of the finished merge publication.
Go take a look.