title: Too many callbacks issue
body: <p>I know that writing async functions is recommended in nodejs. However, I feel it's not so nescessary to write some non IO events asynchronously. My code can get less convenient. For example:</p>
  
  <pre><code>//sync
  function now(){
      return new Date().getTime();
  }
  console.log(now());
  
  //async
  function now(callback){
      callback(new Date().getTime());
  }
  now(function(time){
      console.log(time);
  });
  </code></pre>
  
  <p>Does <code>sync</code> method block CPU in this case? Is this remarkable enough that I should use <code>async</code> instead? </p>