Before I go any further with this post I need to remind you that this update will more than likely patch Root and LOKI bootloader hack when they are released for Verizon and AT&T variants. I would suggest that you just wait for one of the Rom developers to package the update with root and LOKI.
Now onto the good stuff. Samsung is starting to rollout a new update to both international and US versions of the Galaxy S4. This update will address the lack of storage space. Most of the space is taken up by preinstalled Samsung apps. The update allows for app to sdcard. This will go a long way towards saving space on your device. The update will also include new camera firmware, fixes smeering while scrolling, adds HDR video support, adds a new semi transparent status bar, new settings icons and more.