title: IHttpActionResult vs async Task<IHttpActionResult>
body: <p>Most Web API 2.0 methods I've seen return <code>IHttpActionResult</code>, which is defined as an interface that "defines a command that asynchronously creates a System.Net.Http.HttpResponseMessage".  </p>
  
  <p>I'm a little confused about what's going on when a method is returning <code>async Task&lt;IHttpActionResult&gt;</code>.</p>
  
  <p>Why would you use one over the other?  Or are these functionally identical - isn't <code>IHttpActionResult</code> already asynchronous?</p>