MapView - Have Annotations Appear One at a Time

I'm currently adding annotations to my map through a loop... but the annotations are only appearing on my map in groups. Also, on load, only about 4 annotations are actually displayed on the map... but as I move the map a little, all of the annotations that should be there, suddenly appear.

How can I get all of the annotations to load in the right place, one at a time?

Thanks in advance!

Here is the code I'm using to add annotations:

 NSString *incident;
            for (incident in weekFeed) {
                NSString *finalCoordinates = [[NSString alloc] initWithFormat:@"%@", [incident valueForKey:@"coordinates"]];

                NSArray *coordinatesArray = [finalCoordinates componentsSeparatedByString:@","]; 

                latcoord = (@"%@", [coordinatesArray objectAtIndex:0]);
                longcoord = (@"%@", [coordinatesArray objectAtIndex:1]);

                // Final Logs
                NSLog(@"Coordinates in NSString: [%@] - [%@]", latcoord, longcoord);

                CLLocationCoordinate2D coord;
                coord.latitude = [latcoord doubleValue];
                coord.longitude = [longcoord doubleValue];


                DisplayMap *ann = [[DisplayMap alloc] init]; 
                ann.title = [NSString stringWithFormat: @"%@", [incident valueForKey:@"incident_type"]];
                ann.subtitle = [NSString stringWithFormat: @"%@", [incident valueForKey:@"note"]];
                ann.coordinate = coord;

                [mapView addAnnotation:ann];

                [ann release];
                }


// Custom Map Markers
-(MKAnnotationView *)mapView:(MKMapView *)map viewForAnnotation:(id <MKAnnotation>)annotation {

    if ([annotation isKindOfClass:[MKUserLocation class]])
        return nil;  //return nil to use default blue dot view

    static NSString *AnnotationViewID = @"annotationViewID";
    MKAnnotationView *annotationView = (MKAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:AnnotationViewID];

    if (annotationView == nil) {
        annotationView = [[[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:AnnotationViewID] autorelease];
        }

    annotationView.canShowCallout = YES;

    if ([annotationView.annotation.title isEqualToString:@"one"]) {
        UIImage *pinImage = [UIImage imageNamed:@"marker_1.png"];
        [annotationView setImage:pinImage];
        }

    if ([annotationView.annotation.title isEqualToString:@"two"]) {
        UIImage *pinImage = [UIImage imageNamed:@"marker_2.png"];
        [annotationView setImage:pinImage];
        }

    annotationView.annotation = annotation;
    return annotationView;
    }

- (void) mapView:(MKMapView *)mapV didAddAnnotationViews:(NSArray *)views {
    CGRect visibleRect = [mapV annotationVisibleRect]; 
    for (MKAnnotationView *view in views) {
        CGRect endFrame = view.frame;

        CGRect startFrame = endFrame; startFrame.origin.y = visibleRect.origin.y - startFrame.size.height;
        view.frame = startFrame;

        [UIView beginAnimations:@"drop" context:NULL]; 
        [UIView setAnimationDuration:0.4];

        view.frame = endFrame;

        [UIView commitAnimations];
    }
}