Following up on my previous post about adapting pre-Bundler workflows to current best practices, Yehuda Katz posted his suggestions on how to approach Bundler in terms of what you used to do. It’s a good read.
One thing that caught me up was the deployment suggestion to require 'bundler/capistrano' in deploy.rb. If you installed Rails 3.0 soon after it was released, you may still have one of the Bundler 1.0 release candidates. I had RC3, and it didn’t include the Capistrano file, which led to a load error. Update your gem, and all will be well.