Google is expected to debut their newest Nexus device with Android 4.4 KitKit onboard with the months ahead. Meanwhile Samsung has announced that they will be updating the Samsung Galaxy S III and the Samsung Galaxy S4 with Android 4.3 Jelly Bean sometime in October.
Unfortunately Samsung hasn't revealed any other devices which can expect the update. With new devices like the Samsung Galaxy Note 3 and the new Samsung Galaxy Note 10.1 (2014 edition) coming with Android 4.3 onboard and Samsung's plans to extend their Galaxy Gear smartwatch support across to other Galaxy devices, it makes sense that we may see a few more of the lineup getting the update.
source - Samsung | PhoneArena