What's the convention on placing curly braces in Objective-C?

I have seen different conventions for Objective-C (Cocoa/Cocoa Touch) of placing the curly braces.

The two that I have seen are:

- (void)dealloc {
    [super dealloc];
}

vs.

- (void) dealloc
{
    [super dealloc];
}

This confuses me because I would expect that for such a rather small community there should be only one convention.

Which one of the two is more common?