I'm frustrated too!
I stopped at an Apple Store today and the gentleman I spoke with seemed to be unaware of the Updater, or its disappearance.
I do want to stress that he was extremely pleasant and helpful. We went to one of the store's iMacs and he googled it and found a number of announcements from earlier in the week but failed to find it, or any mention of it, on the downloads page. His advice was to check Software Update and the downloads page for its eventual reappearance.
Imagine my surprise when I saw the MacRumors announcement that it was back, only to find that it was another false alarm.
I sympathize with the scale and complexity of this product launch, but I'm anxious to get it all straightened out!