Can't seem to get my HABTM form to work.

What I'm trying to do seems easy, but I've been trying to get it right
for 3 days now, and am at my wits end.

What I have:
2 tables + 1 join table.
Subscribers, Cities, and Cities_Subscribers

Form looks like this:
TEXTBOX - EMAIL
CHECKBOXES - CITIES
SUBMIT

My models are like so:

class Subscriber < ActiveRecord::Base
  attr_accessor :email, :subscriber_id, :city_id
  has_and_belongs_to_many :cities
  accepts_nested_attributes_for :cities
end

class City < ActiveRecord::Base
  has_and_belongs_to_many :subcribers
end

my controller:
  def create
      @subscriber = Subscriber.new(params[:subscriber])
        if @subscriber.save
      flash[:notice] = 'Album was successfully created.'
      redirect_to(:action => 'index')
    else
      flash[:notice] = 'Errors@!!.'
     redirect_to(:action => 'test123')
end
end

My Form:

<%= semantic_form_for Subscriber.new do |f| %>
<%= f.inputs :email %>

<%= f.semantic_fields_for Subscriber.new do |g| %>
  <% @cities.each do |ct| %>
      <label><%= ct.name %>
      <%= check_box_tag "subscriber[city_ids][]", ct.id %>
    </label>

<% end %>
<% end %>
<%= f.buttons %>
<% end %>