title: MKPinAnnotationView callout not showing
body: <p>This is a pretty strange issue, but I think it might be that I don't really understand the finer points of MapKit yet. I have a bunch of annotations on a page. When I select one, I want a callout to appear. I have <code>[pinView setCanShowCallout:YES];</code> and I know that when I tap the pins, they're being selected because the corresponding delegate method <code>mapView:didSelectAnnotationView</code> is being fired. However, no callout pops up! What gives? Any help is greatly appreciated.</p>