Andrew had a great response but I wanted to tweek it a little. The way this is different is that I like my ModelViews to not have overhead data in them. Just the data for the object. It seem that ViewData fits the bill for over head data, but of course I'm new at this. I suggest doing something like this.
Controller
virtual public ActionResult DisplaySomeWidget(int id)
{
SomeModelView returnData = someDataMapper.getbyid(1);
var serializer = new JavaScriptSerializer();
ViewData["JSON"] = serializer.Serialize(returnData);
return View(myview, returnData);
}
View
//create base js object;
var myWidget= new Widget(); //Widget is a class with a public member variable called data.
myWidget.data= <%= ViewData["JSON"] %>;
What This does for you is it gives you the same data in your JSON as in your ModelView so you can potentially return the JSON back to your controller and it would have all the parts. This is similar to just requesting it via a JSONRequest however it requires one less call so it saves you that overhead. BTW this is funky for Dates but that seems like another thread.