title: Most appropriate HTTP status code for "job in progress"
body: <p>What is the most appropriate HTTP status code to give to a client to mean "your request is fine, but it is still in progress;  check back shortly in the exact same place."</p>
  
  <p>For example, say the client submits an initial request to start a heavy query, and the server immediately returns a URL that the client can poll periodically for the result.  In the case the client calls this URL before the job is completed, what is the most appropriate HTTP status code to return?</p>
  
  <p><strong>202 Accepted</strong> would be my first impulse.  Is this the best one, or is there a better one that is more idiomatic for this purpose in REST interfaces?</p>