I’m happy to report that the recent iOS 5.0.1 update has made a dramatic difference to the battery life of my iPhone 4. And I’m hearing that from various other sources too about the iPhone 4, the 4S and even the 3GS.
On Saturday morning, I unplugged my phone. Normally, even though my usage was light, I would have expected it to be all-but-dead by Sunday morning. Instead, I still had about 30% charge by the time I plugged it in again Sunday night. I have never had that experience with any iPhone model I’ve owned (this is my third) or with any previous iOS version. I’d say Apple finally fixed a major problem.
Since the battery life issue was the only one that’s been reported about the iPhone 4S, I’d say that’s resolved and, if you’ve been waiting to get one, you can go ahead.