Is there a definitive list of differences between the Ruby on Rails versions?

Question

Is there a list of the differences between the various versions of Rails somewhere on the web?

I'm working through an older book about Rails that uses Rails 1.2. I know there are other ways to learn Rails these days, but I thought it would be interesting to try and convert all of the exercises in the book to a more modern versions of Rails (I'm currently working with 2.3.5).

A comprehensive list of differences between the various releases would be very helpful. Note that I don't consider the git log a good source of information, as commit messages almost never tell the full story.

Answer 1

http://guides.rails.info/ has release notes for 2.2, 2.3 and 3.0. These summarize the major changes and new features between versions, and will definitely be more concise than looking at git commit messages.

The Riding Rails blog has the release notes for 2.0 and 2.1. I'd link them to you, but I can't because I don't have enough reputation.