HTC One owners on AT&T could be lucky, as they could enjoy the Android 4.3 build before releasing, but only if you are into hacking and know how to root your phone. Recently an OTA build for HTC One users on AT&T has been leaked. It has been made into a flashable zip file, that you could be installing your HTC One in the recovery mode, if you have one. But for dummies you need to root your phone, and replace the stock Android recovery with a third party recovery system.
The changes in the build are quite impressive. And you would be getting the 4.3 gestures before hand. All the gestures are not yet known, as the leak is latest, and not many developers have tried it out.