I keep remembering all the "meh" reactions when Jobs introduced the first iPhone and iPad.
Its hard to predict how this is going to work out. But some thoughts:
Starting at $349. Any bets on how much the 18 karat gold one is going to be? A thousand or more?
Thats a lot of money for a device that, ultimately, is going to be obsolete in three years. And can't be subsidized by your phone carrier. It has some neat features - but enough to persuade hundreds of millions to part with several hundred dollars?
Another problem: Its hard to wear two wristwatches. What does the guy with the $3000 Rolex or Omega - the sort of person who is the theoretical target market for this device - do here? Apple has not only to get these folks to cough up $500 or so for the Apple Watch, but also to leave their fancy other watches at home.
Does Apple need the Apple Watch to be a smash hit? No, they obviously don't. But what would Apple consider to be a success? Five million sold, ten? Anything less than that, and its going to be difficult to build the sort of App "ecosystem" to make this a real game changer.