I think the watch is more likely to be a game-changer than an Apple-produced television set. Apple needs to stick with the set-top box model, but just upgrade the darn thing (including for 4k) and re-do the UI to make it easier for people with large libraries to manage.
Mind you, I know the reason they’ve “neglected” the AppleTV box is that they were a bit more focused on the new phones and watch, and the iOS updates to go with them, along with the OS X updates coming in about a month.
It’s kind of like a variation of Maslow’s hierarchy of needs, where Apple’s “needs” start with a base of “iPhone”, and build up from there to “iPad”, “MacBook”, “Mac”, “iPod”, “Mac Pro”, and “Apple TV”, in roughly that order. (After the initial launch, if it catches on, add the watch probably before iPod.)
The ATV is that need that only seems to be fulfilled when all other needs have been met. :/
Yes, it has changed Pebble's game, as it offers an iPhone compatible watch that does almost all of the functionality of the Apple Watch, requires charging only once a week, and is a third of the price.