Beginning WF: Windows Workflow in .NET 4.0 Book Review

I know I said I would not consider using Windows Workflow until 2011 (Good-bye Windows Workflow Foundation see you in 2011) but I at least wanted to check out the changes. This book is the ideal book for that. It goes into enough detail to give a very thorough understanding of what is going on with Windows Workflow 4.0. The book is very well written and organized. It covers designer-based and code-based workflows, implementing SQL persistence, creating workflow extensions and custom activities, communicating with applications, long-running workflows, and workflows using WCF services. The downloadable code is well organized and very usable. All in all, this is a good book for getting into the guts of WF 4.0. It is a nice introduction.