ches/mongoid_taggable — pull request #10 by ruseel (2012-06-05 08:33:59+00:00)
Title: gem 'mongoid_taggable', git: 'https://github.com/ches/mongoid_taggable.git'

To use your gem (Yes, I wanted to use yours :-) )
Best way I found was changing Gemfile like below

gem 'mongoid_taggable', git: 'https://github.com/ches/mongoid_taggable.git', branch: 'integration'

But this gives me confusion until I figure out. and I guess someone like me fall this pitfall.

So I think, It would be better for you to use 'master' branch on behalf of newbie like me.