Is Pro Django book still relevant?
It's not my place to speak about its worth or recommendations, but I wrote the book with Django 1.0 in mind precisely to make sure it stayed relevant as long as possible. The aspects of Django that I documented are still present and functional, and the general aspects of Python are also still valid. They may have grown additional options along the way, but they shouldn't be removed any time soon or changed in any backward-incompatible way.
That said, I covered some examples of best practices and also some workarounds for things that Django didn't support at the time. Because of new features added to Django since 1.0 was released, these aren't necessarily still the best approaches anymore. So feel free to read it for the factual descriptions of how things work, but take the recommendations with a grain of salt and always consult the official documentation for the latest features.
I want to dig deeper into Django's internals and the official online documentation only goes so far toward that end. 
The reviews for Marty Alchin's Pro Django are fantastic (I've read Pro Python and really enjoyed it). However, the book is from 2008 and is based on Django v1.0.  My company builds off v1.3. 
Is this book still worthwhile?  How can I best learn about Django's meta-programming (beyond looking through the source code, which I am also doing)?
Thanks