My reasons for getting an iphone 5 are in this order
LTE (ability to keep unlimited plan with ATT, I know they throttle after 5GB but I doubt I will ever get there)
Screen improvements
Build improvements, no longer a glass back
Processor improvements
Camera improvements
The most important reason, somehow even though I purchased my iPhone 4S on the contract price last year, all my lines are eligible for an upgrade this time. Not really sure how that happened but I am glad it did.
