They aren't stealing thunder from Apple. They're just giving credence to iOS users (and people going to iOS from Feature Phones and other Smartphone Platforms) satisfaction with not having to hear about their phone becoming old news 2-4 months after they pre-order it.
Samsung has denied this rumor (Lol), but it does affect the way people think about your products when you're constantly developing devices and effectively downgrading flagships in the mind of the consumer. They did this with the Vibrant and Vibrant 4G on T-Mobile, and a lot of people were not happy about it. HTC was also guilty of the same thing, too, and Motorola was king of releasing phones in breakneck pace (Razr, then Razr Maxx for the win!).