The models are embedded one to many. User model embeds_many :watchlists and watchlist embedded_in :user The user is returning this error if not present :

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2011-09-17T21:07:11+00:00 app[web.1]: NoMethodError (undefined method `save!' for User:Class):
2011-09-17T21:07:11+00:00 app[web.1]: app/models/user.rb:28:in `create_with_omniauth'
2011-09-17T21:07:11+00:00 app[web.1]: app/controllers/sessions_controller.rb:10:in `create'
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