The advantage for using NFC instead of email is that the files could be transferred even when there is no internet connection. Using NFC, the locked files are transferred to the gift iOS device. Once your friend (or family member) is back within range of an internet signal, the file is authenticated and the digital "present" ready to be opened. The application, titled "Media gifting devices and methods," covers gifting content and media directly from iTunes and the gifting of media already downloaded on the sender's device. Right now, there is no method that will "gift" digital media directly from one iOS device to another.
The patent application doesn't guarantee that NFC will be enabled on the next generation of iOS devices, but it certainly is a positive sign for those hoping for the feature on their next iPhone.
source: USPTO via AppleInsider