confused with facebook json object with jquery and nodejs

writing my first facebook/node/express app

With express I'm using

 app.post('/friends', function(req, res) {
        graph.get("/me/friends?fields=id,name", function(err, res2) {
         res.send(res2);
     });
 });

client side I'm using

 $('#getFriends').click(function() {
      $.post('/friends', function(data) {
           console.log(data);
           console.log(data.length);
      });
 });

With a previous app, I called the graph from the client side with getJSON and looped through everything with a for loop to print out the id and name. With this, I'm confused. Do I need to convert it to an array or a string first? Am I using the express request properly? It logs the data object, but even when I go to print the length it's null.