Like a technology zombie I stumbled to my computer and pre-ordered the iPhone 4S as soon as I was able to. I used the excuse that I'm gonna do more iOS app development and it will be good to have the latest phone for testing. But, the real reason is that I'm a nut.
Was it worth it. For people with an iPhone 4, probably not. iOS 5 is a major upgrade that will keep the iPhone 4 users happy for a long time.
The one major reason to get the iPhone 4S is for the camera upgrade. The improved resolution and performance combined with the Camera improvements in iOS 5 are all great reasons to get the new phone.
What about Siri? It's freaking wonderful. It does a great job of recognizing voice and converting it to text. And I hope that once it leaves Beta it will become available to more Apple devices (crosses fingers for iPad 2 support). Apple will most likely add support to many more applications. Siri's syntax will improve and include many more things you can ask it to do.