title: Correct way of using @autoreleasepools?
body: <p>I would like to know if the following code is a good way to use the new <code>@autoreleasepool</code>, should I use it this way or let the main autoreleasepool take care of the objects?</p>
  
  <ul>
  <li>(void) callingAutoReleasedObject, would probably be my viewDidAppear, or similar function.</li>
  </ul>
  
  <p>Thanks!</p>
  
  <pre><code>- (UIBarButtonItem*)backButton {
      UIBarButtonItem* backButton = [[UIBarButtonItem alloc] initWithTitle:@"CustomBackTitle"
                                                                     style:UIBarButtonItemStyleBordered
                                                                    target:nil
                                                                    action:nil];
      return [backButton autorelease];
  }
  
  - (void) callingAutoReleasedObject {
  
      @autoreleasepool {
          [[self navigationItem] setBackBarButtonItem:[self backButton]];
      }
  }
  </code></pre>