If you are a pro, novice or someone who just wants to know more about WCF, you should check this out - Essential Windows Communication Foundation (WCF): For .NET Framework 3.5 http://www.amazon.com/gp/product/0321440064/.  Microsoft's Steve Resnick, Richard Crane and Chris Bowen, of the Microsoft Technology Center in Boston, wrote this gem.  Congrats to my colleagues and best wishes for success with your book!  Now who's going to write the next WCF book?!