I have been asked for a number of references that would be valuable for someone just getting started with SharePoint workflow. So, as I have been developing demos and discussions I put together a series of references that I thought I'd share more broadly. If I have missed a good one then email it to me and I'll add it to the list. In general, I would strongly encourage folks to look at the WSS v3 and MOSS SDKs, but I know that this can be a lot to swallow first time around. Hope they are useful......
Introduction / Overview
Learn the basics of the Windows Workflow Foundation, how this technology has been integrated into both Windows SharePoint Services and the 2007 Office System, and how to benefit from workflows applied to business processes.
Get a high-level overview of how Microsoft Windows SharePoint Services (version 3) implements the workflow capabilities of the Windows Workflow Foundation, and how Microsoft Office SharePoint Server 2007 extends those capabilities with symmetrical Microsoft Office InfoPath 2007 forms.
Although WSSv3 supports workflow on libraries and list, SharePoint Designer is required to build the workflow. A MOSS 2007 Team Site, on the other hand, provides a browser based interface for the list/library manager to build a workflow. MOSS 2007 provides a number of workflows available to any list/library in the site collection.
Workflow Activation / Development Tools: SPD and VS2005
Workflow Creation and Customization: Visual Studio 2005 vs SharePoint Designer 2007
(taken from WSS v3 SDK and paraphrased)
Authored in the VS designer as a template which can be associated with multiple sites, lists and content types.
Wizard-driven interface to author and bind workflow to a specific list or library at time of creation. No association with other lists.
Sequential, State Machine
Create Custom Activities and Conditions
No. Must use a predefined set of activities and conditions.
Yes. Visual Studio debugging.
No step-by-step debugging available.
Workflow markup file and code-behind files are compiled into workflow assembly that is deployed to the MOSS server.
Workflow markup, workflow rules, and supporting files are stored uncompiled in a specific document library on the site and compiled on demand.
Dynamic Data Gathering and Workflow Modification
Can use any forms technology, such as InfoPath 2007 or ASP.NET 2.0 forms. Modification to a running workflow is possible.
Automatically generates ASP.NET 2.0 forms, which can then be customized. Modification is not possible.
Package workflow assembly and workflow definition as a SharePoint Feature and deploy to the site.
Automatically handles deployment to specific list or library.
Tutorials and Samples
(including the white paper "How to import custom actions into SharePoint Designer)
Architecture and Internals