Interesting Things
Switching to Bundler 0.9.x?
If your old gem definitions use :lib => false, don't forget to change it to :require => false
Additionally, older versions of Bundler use the deprecated named argument :require_as (instead of Rails' :lib and Bundler 0.9's :require) to override the path that Bundle requires for you.
Here is an example of how to tell Bundler 0.9.x not to require a gem automatically:
gem "leetsauce", :require => false