jquery not loading (tokeninput) in Rails app

Question

I'm trying to follow along with the instructions on how to implement jquery-tokeninput here:

How to use jquery-Tokeninput and Acts-as-taggable-on

I am trying to attach tags to a "post". I can use the text field in my form to create new tags. However, the javascript just will not fire at all. It's as if none of the code even exists. I don't get any error messages. The text field just acts as a normal text field with no javascript events firing. What can be the issue? Here is my relevant code:

post model

attr_accessible :tag_list
acts_as_taggable_on :tags

posts controller

def tags 
    query = params[:q]
    if query[-1,1] == " "
      query = query.gsub(" ", "")
      Tag.find_or_create_by_name(query)
    end

    #Do the search in memory for better performance

    @tags = ActsAsTaggableOn::Tag.all
    @tags = @tags.select { |v| v.name =~ /#{query}/i }
    respond_to do |format|
      format.json{ render :json => @tags.map(&:attributes) }
    end
  end

routes # It has to find the tags.json or in my case /products/tags.json get "posts/tags" => "posts#tags", :as => :tags

application.js

$(function() {
  $("#post_tags").tokenInput("/posts/tags.json", {
    prePopulate:       $("#post_tags").data("pre"),
    preventDuplicates: true,
    noResultsText:     "No results, needs to be created.",
    animateDropdown:   false
  });
});

Out of frustration I also created a posts.js.coffee file just to see if that was the problem:

$ ->
  $("#post_tags").tokenInput "/posts/tags.json",
    prePopulate: $("#post_tags").data("pre")
    preventDuplicates: true
    noResultsText: "No results, needs to be created."
    animateDropdown: false

post form view

<%= f.label :tag_list %>
<%= f.text_field :tag_list, :id => "post_tags", "data-pre" => @post.tags.map(&:attributes).to_json %>

Am I missing something here? Any help would be greatly appreciated!!!

Thanks!!