title: Conditional Layout Blocks in Magento depending if logged in?
body: <p>What is the easiest/most recommended way to have some conditional layout logic based on if a user is logged or not?</p>
  
  <p>eg.. in pseudocode</p>
  
  <pre><code>if (customer logged in)
    display this custom onepage checkout layout block
  otherwise
    display this other custom layout block (for guests)
  </code></pre>