When there's a new version of any software I usually shudder and shy away from it. Trouble free upgrade paths can happen, but sometimes it doesn't. Granted normal "computer software" tends to be quite stable these days. The more "low level" the software is, the more can (and thus will) go wrong.
When I saw that Rails 2.2.2 was out, I had to take the back-seat for a while and wait for the storm to pass. Today I took the plunge. I upgraded my dev machine to Rails 2.2.2 and to my surprise the problems were minimal! First thing I had to do was run gem install rubygems-update and then update_rubygems to get the gem system up to 1.3.1 a normal gem update --system wouldn't do. This was well documented on the 'Net though - no problems. Then I changed the RAILS_GEM_VERSION line in environment.rb to reflect the new version of Rails.
The only real problem I've stumbled upon so far is that the Inflector stuff has changed. I had to change Inflector.inflections do |inflect| in environment.rb to ActiveSupport::Inflector.inflections do |inflect|, that's it. Why this change has been made I don't know, but I'm glad I didn't have to spend much time on it.
Easiest Rails upgrade so far..?! Thanks guys!!