title: IsolatedStorageSettings.ApplicationSettings doesn't get stored to restart
body: <p>I'm writing a WP7 (Mango) application.
  I store values in WP7 IsolatedStorageSettings.ApplicationSettings, then I call  <code>IsolatedStorageSettings.ApplicationSettings.Save();</code>  </p>
  
  <p>If I press back, and leave the screen, and I come back I can read values just fine.
  However if I press restart in the debugger (or just restart from the emulator) the ApplicationSettings throws a <strong>KeyNotFoundException</strong>, <em>as if it didn't persist</em>...<br>
  I haven't yet tried it on device, I don't have one available right now.</p>
  
  <p><strong>What can I possibly be doing wrong?</strong></p>