Apple issued a statement to The Loop's Jim Dalrymple about customer complaints of poor battery life with the new iPhone 4S and iOS 5:
There have been a litany of complaints about iPhone 4S and iOS 5 battery life ever since their release last month. A number of solutions have been proposed by the community for this problem, including turning off Time Zone detection, Bluetooth and others.A small number of customers have reported lower than expected battery life on iOS 5 devices. We have found a few bugs that are affecting battery life and we will release a software update to address those in a few weeks."
Apple has already seeded developers with a 5.0.1 beta that is said to address the issue.
Article Link: Apple Confirms Battery Life Issues With iOS 5, Software Update Coming