Essentially, yes. To the best of my knowledge, there haven't been any major changes to the Django Book since it was originally published. One of the reasons for releasing the book as open source was to allow (and encourage) the community to submit updates. I'm pretty certain that there weren't that many updates prior to the book source being put on GitHub, so the Github commit history will show you all the changes that have been made.
If you do go through the release notes for 1.1, 1.2, 1.3 and 1.4, you shouldn't find *that* many backwards incompatibilities. Off the top of my head, I can only think of a few items that would make a significant difference to the content of the Django book:
* Import syntax at the top of urls.py
* Quoting syntax in {% url %} tags
* The method of installing admin urls
* Allowing for CSRF in forms
There have been other backwards incompatibilities, but they tend to be fairly esoteric edge cases; there have also been lots of additional features, which means the current content of the Django book may not reflect best practice (e.g., the syntax of {% if %} clauses in templates). However, as a project, we've been strict about backwards compatibility, so there shouldn't be much that doesn't work *at all*.
That said, we would certainly welcome any contributions to help get the Django Book up to date, reflecting current best practice, and ironing out the incompatibilities that have emerged over time.
Yours,
Russ Magee %-)