For some reason we're looking for a computerized wrist watch. I guess it's because everyone, at least before smart phones, used to buy a watch. The market for wrist watches appears to include just about everyone, but good quality watches are rarely replaced. It's becoming a niche market steeped in nostalgia.
A watch is for telling time. A computer isn't necessary for that function. No one needs an iWatch to tell time. The current networked wearables are small feature-reduced smart phones that can be strapped to the wrist. Not that phones are still telephones.
The etymology of the word “watch” isn't entirely clear, but it seems to have something to do with a schedule for keeping watch, for instance on the deck of ship. An iWatch would be a device for keeping an eye on the wearer. The schedule can be discarded because it's always on, although the batteries need to be recharged now and then. “Wearable” means attached via a strap or some other means–it's a device not meant for the hand or the pocket.
These new devices, if they actually appear, are personal data collection devices that will send information for analysis to a personal or feudal cloud. The devices themselves will have limited read-out capability. They are sensors. They're meant to suck in data, not to display it. And once it's “in,” there's little chance it will remain private.