Got 4.3 on my HTC One yesterday - love it!
Thx HTC, great job. Blinkfeed is getting better and better (now with G+ support) - and I love the enhancements to ZOE. Great update! And now hurry, KitKat is waiting.
Btw, as a long time Nexus lover (being an Android dev) I've never regretted buying the One. Comparing it with my co-workers N5s it is still FAR superior in every way.