New developer resources that is.  These are just some that I've looked at recently but here are my recommendations...

The Good:

Quick Recipes on Symbian OS 

This book is designed as a 2 week self-study course for Symbian C++.  There's a section to get your development environment set up and working and then the basics of Symbian C++ are all covered in the first 75 pages.  After that you can work through, or pick and choose from a number of 'recipes' - which are code examples like you'd get on the wiki here but with more explanation.  The recipies cover File Handling, Contacts & Calendar, Networking, Messaging, Graphics & Drawing, 3D Graphics Using OpenGL ES, Multimedia, Telephony, Connectivity and Location-Based Services.  Some of the material was contributed by fellow Champion Antony Pranata and other parts by FN's own Jukka Silvennoinen (the amazing symbianyucca on the DiBo).  I've been lucky enough to get an advanced copy but you should be able to buy yours very soon!  If you like to take a hands-on approach to your learning then this is the book for you.

The Bad:

Platform security for all

A new developer booklet from Symbian - although I've linked it above, don't read it!  You'll probably end up more confused about platform security than you were before.  The diagram on the front cover is a classic example, it's just wrong.  The key that goes with it inside (page 8) compounds the original sin of PlatSec - the secure core that is trusted with all capabilities and the capability that allows the creation of executables and granting of other capabilities have the same name (TCB) when they are different things - this diagram makes the difference less clear, not more.  The other big problem with this diagram is that it shows the capabilities in a heirarchy, when they are supposed to be orthogonal (i.e. separate, not layered on top of one another).  Anyway, enough ranting, I'll just say that spreading mis-information about a security system doesn't make it more secure and Symbian should withdraw this booklet.

The Ugly: 

UIQ 3: The Complete Guide

Finally, the most unappealing book to buy on Symbian OS (it's not as bad as the PlatSec booklet above, but that's not for sale) is the recent UIQ 3 book.  There are a number of reasons for this, not all related to the quality of the material (some of it's good, some bad - note that despite having their name stamped on it, it's not an offical Symbian Press title).  An important one is that most/all of the content is being made available on-line as a wiki.  The other, is that, following the recent Symbian Foundation announcement, UIQ is as good as dead.  Unfortunate timing for the release of the book.  There will still be some UIQ phones around for a while but the volumes are not that high.  I'm sorry to say for UIQ device owners - investing in UIQ software development is likely to be a waste of money.  Develop for S60 and port to UIQ only if there is a real demand from end users.

There are of course many other great books and booklets on Symbian development - this is just my attempt to help you use your reading time wisely.

Mark