title: Issue with Mongoose model.save callback
body: <p>I am learning Node.js with a book. Instead of coping and using the book sample code as it is I am using the basis and reusing in own code used as learning exercise.</p>
  
  <p>I have this code for a new user creation, I will copy what I believe are the relevant.
  What I expect to happen is that user.register uses model.register and receive a true or false depending if the user was created or not and sending a response accordly</p>
  
  <p>app.js capture the post</p>
  
  <pre><code>app.post('/user', users.actions.register);
  </code></pre>
  
  <p>user.js register</p>
  
  <pre><code>var register = function ( req, res ) {
      if ( req.body.username === '' || 
          req.body.email === '' || 
          req.body.password === '' ) {
  
          //Some field is blank - insufficient information
          console.log('User creation failure: Insufficient data');
          res.json(400);
  
      } else {
  
          var newUser = new models.account.user ({
              username: req.body.username,
              email: req.body.email,
              password: req.body.password
          });
  
          models.account.register ( newUser, function (succ) {
              console.log (succ);
              if ( succ === true ) {
                  res.json(200);
              } else {
                  res.json(400);
              }
          });
      }
  };
  </code></pre>
  
  <p>then account.register</p>
  
  <pre><code>var register = function ( newUser ) {
      console.log ('Save command sent.');
      newUser.save ( function ( err ) {
          if (err) {
              console.log(err);
              return false;
          }
          console.log('User Created');
          return true;
      });
  };
  </code></pre>
  
  <p>The user gets created on the database, and the output on the console is </p>
  
  <pre><code>Save command sent.
  User Created
  </code></pre>
  
  <p>What I was expecting to happen is that succ receives true or false, but I am doing something wrong and cant figure out why.</p>
  
  <p>I made this code works changing the approach, but since this is a learning experiment for me I wanted to be able to do it this way.</p>
  
  <p>I would appreciate if someone could point me in the right direction or show me what I am doing wrong.
  Thanks.</p>