iPhone 4S weekend sales top 4 million

... and 25 million devices already running iOS 5.

Apple has announced that weekend sales of it's new iPhone 4S topped 4 million.

Philip Schiller, Apple's senior vice president of Worldwide Product Marketing, breaks the good news [emphasis added]:

iPhone 4S is off to a great start with more than four million sold in its first weekend-the most ever for a phone and more than double the iPhone 4 launch during its first three days. iPhone 4S is a hit with customers around the world, and together with iOS 5 and iCloud, is the best iPhone ever.

Wondering why downloading iOS 5 has been a little flakey over the past few days? Maybe this will explain:

In addition, more than 25 million customers are already using iOS 5, the world's most advanced mobile operating system, in the first five days of its release.

What about iCloud?

... more than 20 million customers have signed up for iCloud ...

While the iPhone 4S didn't live up to the blogosphere-generated hype that preceded it, and it wasn't called the iPhone 5, it looks like none of this put a damper on sales.

What do you think the big selling point was? Siri? Better camera? Or is it that the competition is so severely lacking?