Apple has released a software update for the iPhone 5 that features only one noted change. iOS 6.1.4 isn’t available for any other iPhone models and states that it includes and ‘updated audio profile for speakerphone’.
So it’s probably worth updating just because you’re going to want to keep your device up to date, but don’t expect anything major.
You can download the update directly here or use the Settings>General>Software Update tool on your device. The last update that Apple released was iOS 6.1.3 in March, which fixed a lock screen bypass bug and some of the vulnerabilities that were being used for the Evasi0n jailbreak.