Another CE6 book is getting ready to be released - the book is called Professional Microsoft Windows Embedded CE 6.0 (ISBN: 978-0-470-37733-8) and is written by Samuel Phung who works at ICOP who are also part of the Windows Embedded CE 6.0 SPARK program
Other books/content that might be interesting for you are:
CE 6.0 Fundementals, Doug Boling (blog link) Programming Windows Embedded CE 6 (application development), Paul Yao .NET Compact Framework Programming with C# (application development), CE 6.0 exam preparation kit (PDF) - hopefully I didn't miss any.. let me know if you are aware of other useful/interesting CE 6.0 content.
Here's a breakdown of the chapters in the book, which is expected to be released in November of this year (480 pages).
1. Windows Embedded CE.
2. Development Environment and Tools.
3. Board Support Package.
4. Building a Customized CE 6.0 Runtime Image.
5. Connecting to Target Device.
6. Debugging and Debugging Tools.
7. Boot Loader Overview.
8. The Registry.
9. Testing With CETK.
10. Application Development.
11. Visual C# 2005 Applications.
12. VB 2005 Applications.
13. Native Code Applications.
14. Autolaunch Applications.
15. Customizing the UI.
16. Thin-Client Applications.
17. Home Automation Applications.
18. RFID Security Access Control Applications.
19. Robotic Applications.
20. Deploying a CE 6.0 Device.
Appendix A. Windows Embedded CE References.
Appendix B. Installation and Software.
Appendix C. Sample Applications and OS Design Projects.
It's interesting to see the amount of content being developed/printed around CE 6.0 when compared to the number of books/content available for CE 5.0.