I was just on Amazon and it looks like the follow up to Windows Communication Foundation: Hands On! is now available for pre-order.
This book contains all of the content updated for RTM, plus 200+ more pages than the original. You'll also see that we've got a new co-author, Matt Winkler.
For those unfamiliar with Matt, he's the technical evangelist for Windows Workflow Foundation here in Redmond, and he's added some great WF content to the book.
If you want to get more details, you can find it here:
http://www.amazon.com/Windows-Communication-Foundation-Unleashed-WCF/dp/0672329484/sr=1-3/qid=1170008872/ref=sr_1_3/002-4228351-3336016?ie=UTF8&s=books