Updating two divs?

Use RJS to do that:
class PersonController < ApplicationController
  def create_address
    // save address to DB

    render :update do |page|
      page.replace 'addresses-list', :partial => 'address', :collection =>
@addresses
      page.remove 'address-form'
    end
  end
end

or in app/views/person/create_address.rjs :

page.replace 'addresses-list', :partial => 'address', :collection =>
@addresses
page.remove 'address-form'

In later case, write this to controller's action:

class PersonController < ApplicationController
  def create_address
    // save address to DB

    respond_to do |format|
      format.js
    end
  end
end