Documentation for simply_helpful features rolled into rails 2

Hi All,

In Ryan Bates screencast episode 80 (Ruby on Rails Screencasts - RailsCasts 80) on simplifying views in rails he mentions that

<% render :partial =>'product' , :collection => @products %> and <% render :partial =>'product' , :object => @product %>

can now be written as

<%= render :partial => @products %> and <%= render :partial => @product %> respectively.

He also says that <%form_for :product, :url -> products_path do |f| %> and <%form_for :product, :url =>product_path(@product), :html => {:method => 'put'} do |f| %>

can now both be written

<% form_for @product do |f| %>

Can anyone tell me where this is documented since the api only mentions the old ways as far as I can see unless I am looking in the wrong place.

Many thanks

Anthony