Ruby on Rails 3 may be different from Ruby on Rails 2, but Ruby on Rails 3 has been around for 2 years now (see Ruby-on-rails vs ruby-on-rails3), so I think every question tagged with
ruby-on-rails is about version 3 now. So why do we still have both a tag
ruby-on-rails (63183 questions) and a tag
ruby-on-rails-3 (21137 questions)?
If the question is specific about the current version, I expect it only have the
ruby-on-rails tag. Another tag for the version is only helpful if it's not about the current version, e.g.
ruby-on-rails-2 (145 questions).
So why do we still need the tag
ruby-on-rails-3 with 21137 questions? can't we make it a synonym to
In my perspective, a version in it's own tag isn't very informative, it's enough to have the version noted in the question. People that follow
ruby-on-rails will know when the problem is version specific and people working with other versions will understand most of the content anyway.