I'd say the watch is similar to the iPod; there was competition out there but the general public didn't really care. Then the iPod was released and commentators complained it was less capable and more expensive than its rivals (insert famous slashdot quote here). But the people who bought it loved it and Apple iterated on the design. (With the watch there are a number of studies that say that tech people don't like it but non-tech people love it - personally I sold mine and won't get another till the screen is on constantly and its thinner).

The question is whether the watch repeats the iPod trick of dominating and expanding the market two iterations on. With the iPod this happened when it was no longer tied to the Mac, maybe with the watch that will happen when it's no longer tied to the iPhone?