AnandTech claims both the HTC One and the Samsung Galaxy S4 from Google Play are currently receiving OTA (over-the-air) update notifications. For the Samsung Galaxy S4 the update is around 150MB and for HTC One it's 180 MB.
The update lands in immediately after both HTC and Samsung released the Android 4.3 kernel sources online, according to the site. The Android 4.3 update for both devices have been developed by the OEMs and have no changes to the user-interface.
When Google announced the Google Play Edition devices, it promised quick updates on the device and a complete stock Android experience. With this update the Google Play Editions of Samsung Galaxy S4 and HTC One joins the list of devices running Android 4.3 that only included Nexus devices until now.
The Android 4.3 update comes with some new features like restricted profiles which enables users to restrict app usage and content consumption on an Android device, dialpad autocomplete that adds the autocomplete feature in the dialpad suggesting contact names or phone numbers when users start keying-in something, keyboard and input which now comes with an upgraded algorithm for tap-typing recognition that makes text input easier while chatting via messages or even while composing emails and new camera UI that offers a new updated Camera app that features a new arch based menu which makes it easier to control and switch camera settings.
(Also see: 10 new features in Android 4.3 Jelly Bean)