title: json.net vs DataContractJsonSerializer
body: <p>I know there's a DataContractJsonSerializer that comes now with the .net framework and is used by wcf ajax enabled services. However, I've noticed there's also a json.net project over at <a href="http://json.codeplex.com/" rel="noreferrer">codeplex</a>.
  I'm wondering if there are any advantages or features that are present in the codeplex project that are missing from the .net framework. </p>