Comecei a estudar sobre o assunto, mas por enquanto só tenho links:
http://msdn.microsoft.com/en-us/library/bb410772.aspx
http://msdn.microsoft.com/en-us/library/bb410782.aspx
http://msdn.microsoft.com/en-us/library/ms735927.aspx
http://msdn.microsoft.com/en-us/library/ms741723.aspx
http://msdn.microsoft.com/en-us/library/ms735967.aspx
http://imasters.uol.com.br/artigo/6794
http://imasters.uol.com.br/artigo/6864/dotnet/windows_workflow_foundation_-_parte_02/
http://netfx3.com/content/WFHome.aspx
http://mdalab.wordpress.com/2007/11/11/as-vantagens-reais-do-windows-workflow-foundation-wf/
http://msdn.microsoft.com/en-us/library/bb410782.aspx
http://msdn.microsoft.com/en-us/library/ms735927.aspx
http://msdn.microsoft.com/en-us/library/ms741723.aspx
http://msdn.microsoft.com/en-us/library/ms735967.aspx
http://imasters.uol.com.br/artigo/6794
http://imasters.uol.com.br/artigo/6864/dotnet/windows_workflow_foundation_-_parte_02/
http://netfx3.com/content/WFHome.aspx
http://mdalab.wordpress.com/2007/11/11/as-vantagens-reais-do-windows-workflow-foundation-wf/
http://blogit.create.pt/blogs/tiagooliveira/archive/2008/03/09/Webcasts-WF-_2D00_-Materiais.aspx
Em breve estarei postando alguns exemplos de como utilizar .
Arquitetura e Desenvolvimento de Software 