Why will option 1 works and option 2 will not (I'm going to kick myself when its pointed out I think) punctuation put in to keep rsl happy ;-)

## Option 1 ##

def show
  @page = Page.find(params[:id])
  @css_class = @page.css_class
  respond_to do |format|
    format.html
    format.js { render :update do |page|
      page.hide 'page_content'
      page.hide 'gradient'
      page.replace_html 'gradients', :partial => '/layouts/gradient'
      page.replace_html 'page_content', :partial => 'show'
      page.replace_html 'page_image', :partial => 'crossfader'
      page.call 'displayfader'
      page.visual_effect :appear, 'page_content'
      page.visual_effect :appear, 'gradient'
      end }
  end
end

## Option 2 ##

CONTROLLER
def show
  @page = Page.find(params[:id])
  @css_class = @page.css_class
  respond_to do |format|
    format.html
    format.js
  end
end

TEMPLATE
      page.hide 'page_content'
      page.hide 'gradient'
      page.replace_html 'gradients', :partial => '/layouts/gradient'
      page.replace_html 'page_content', :partial => 'show'
      page.replace_html 'page_image', :partial => 'crossfader'
      page.call 'displayfader'
      page.visual_effect :appear, 'page_content'
      page.visual_effect :appear, 'gradient'