After the firmware update for I950XXUAMDK, now Galaxy S4 I9505 firmware has been released. You can download I9505XXUAMDM update and flash it on your device. You can update your device using Samsung Kies or can download and install it manually using Odin. This is the first firmware update that was made available for download. The build date is April 25th so it should be latest one for now. Here are the details:
Version: Android 4.2.2 Jelly Bean
Date: April 25th, 2013
Download and Install I9505 XXUAMDM: Galaxy S4 Germany Update
You can try updating your device to XXUAMDM firmware using Samsung Kies. If the update is not yet available in Kies, you can download and install it manually. The download link for firmware is provided below:
Important: It should be noted that this firmware update is meant for Galaxy S4 I9505 (powered by Snapdragon) devices and you should not try to install it on any other variants of SGS4.
Download Firmware Package: I9505XXUAMDM_I9505OXAAMDM_DBT.zip
After downloading, unzip the file to get I9505XXUAMDM .tar.md5 file(s). Then use Odin to flash firmware on your device. A detailed step by step guide with instructions is provided at following link: How to install stock ROM using Odin.