Folks who own the Google Play Edition of the HTC One M8 or the HTC One M7 will soon be happy to find a new update on their device. The Android 4.4.4 version of KitKat is now pushing out to those devices.
The primary thing this update addresses is a few security vulnerabilities, including HeartBleed. You will probably want to turn on WiFi in order to insure the smooth delivery of your update. If you want to manually check for it you can do the usual: Settings > About phone > System.
Sound off here and let us know when you have the update.