HTC One got the update, now its S4's turn. Samsung released the Android 4.4 KitKat update for the Galaxy S4 Google Play edition. The main reason for getting a Google Play edition device is that you will recieve all updates almost instantly of their release and so far this is the case.
Here is the official statement from Android on Google+:
"Starting today, Samsung GS4 and HTC One Google Play edition devices are getting an update to Android 4.4! Learn more about Android 4.4, KitKat: http://www.android.com/versions/kit-kat-4-4"
Source: Android
More info: gsmarena