In several pieces of sample objective-c code I've seen people create new objects like this:

RootViewController *viewController = [[RootViewController alloc] init];
self.rootViewController = viewController; // self.rootViewController is a (nonatomic,retain) synthesized property
[viewController release];
[window addSubview: [self.rootViewController view]];

Is that any different "behind the scenes" than doing it like this instead?

self.rootViewController = [[RootViewController alloc] init];
[window addSubview: [self.rootViewController view]];

Seems a bit more straightforward/streamlined that way so I'm wondering why anyone would opt for the first method.

Thanks!