I've written on .NETCF in a past lifetime. .NETCF is a cool little technology (no pun intended). But, it had been a good while since I have read a .NETCF text of any size. But, I had one sitting on my desk, so over the holidays (with a upcoming demo that I had to write) I cracked open Microsoft Mobile Development Handbook (MsPress), authored by Andy Wigley, Daniel Moth, Peter Foot. It's a MsPress book, but that doesn't bias me because I'm tough on who/what I read. I am biased a little due to knowing and respecting these authors from my days in the MVP program; but, seeing their depth and experience on .NETCF is why I respect them. I also have been a fan of Andy because of liking his previous books on .NETCF and ASP.NET Mobile Controls.
This book does not disappoint. Yes, it has been out for 6 months and .NETCF 3.5 has come out since (they do cover the highlights though), but the Window Mobile development background is there AND this is critical. Anyone can take VS and churn some managed code - but there are plenty of opportunities to make bad choices. That's why I recommend this book. It's done with enough detail that 624 pages serves as a reference, but it's structured in such a way that the experienced mobile developers can go where they need to. There are many valuable sections in this book, but the performance, debugging (logs), security, and graphics chapters make the book more than worth the price. They also have some great reviews on the book sites.
Congratulations, my friends - another home run.