Estoy usando el siguiente código para configurar un banner de iAd compartido.

AppDelegate.m

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    _adView = [[ADBannerView alloc]init];
}

ViewController.m

-(void) viewWillAppear:(BOOL)animated {
    AppDelegate *appdelegate = (AppDelegate *)[[UIApplication sharedApplication ]delegate];
    _adView = [appdelegate adView];
    _adView.delegate = self;
    self.canDisplayBannerAds = true;
}

- (void)bannerViewDidLoadAd:(ADBannerView *)banner {
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:1];
    [banner setAlpha:1];
    [UIView commitAnimations];
}

- (void)bannerView:(ADBannerView *)banner didFailToReceiveAdWithError:(NSError *)error {
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:1];
    [banner setAlpha:0];
    [UIView commitAnimations];
}

bannerView:didFailToReceiveAdWithError se llama como se esperaba perobannerViewDidLoadAd nunca se llama. Estoy tratando de mover algunos botones hacia arriba en la pantalla cuando se carga el banner de iAd.