It's now up to AT&T, Sprint, T-Mobile, and Verizon. The Android 4.4 KitKat update for the HTC One is finalized and shipped off to the carriers. HTC announced that it finished all of its work on the project and put the ball in the court of the Big 4. We should begin to see updates roll out as early as next week, although of course that depends on how long the vetting process of the carriers actually takes. Historically speaking Sprint and AT&T tend to be first, with T-Mobile a close second, and Verizon bringing up the rear by a wide margin.
Keep in mind that even when the update begins to roll out for your carrier, it might take a week or two for you to finally get it. They usually send them out in waves. We will let you know as soon as we start to see them hit the airwaves.