title: knockout.js using a ko.observable via a selected value in a ko.computed statement
body: <p>I am trying to achieve the following with knockout with some difficulty:</p>
  
  <ol>
  <li>Bind a select form element ... this works</li>
  <li>Display the selected option via a ko.observable ... this works</li>
  <li>Use the ko.observable from #2 inside a ko.computed variable... I cant figure this out.</li>
  </ol>
  
  <p>Here is a <a href="http://jsfiddle.net/W2ABG/" rel="nofollow">Fiddle</a> of my attempt so far. any ideas?</p>