Back in the day, plugins were an acceptable way to extend Rails because gems were hard to create and publish. It was easier to just put up a public repo and have people pull a plugin from there.
In Rails 3, I think that we’ve got a good solution to these problems. Bundler allows us to type bundle gem and quickly get the skeleton of a gem. Bundler also also allows us to easily pull in unpublished gems via the :git option from any public git repo. The new rubygems.org allows us to easily publish gems that are ready for prime time.
Yes plugin maintainers will need to take a little time to update their plugins to be gems but I think that time is outweighed by the benefits of less code in Rails (because the plugin architecture code will be removed), possibly increased startup time because less code is running and adhernace to a standard way of loading Ruby extensions via the gem mechanism.
What do people think?
A lot of hard work has gone into modularizing the Rails3 codebase to make it easier to work with and faster.
Do we continue the spring cleaning and get rid of other remnants from the past?