I don't know how the rumors that Apple is making a watch got started. I supposed it started when the iPod nano was so small that it could be fitted on a wrist band and be worn as a watch. It didn't do much except tell time.
Then you've got the Pebble watch that got a lot of media attention via its success Kickstarter campaign. Of course, when I dug deeper, there are plenty of watches out there that has similar capabilities.
I suppose that's how it all got started. So everyone is making a watch. Heck, Amazon, too! I think some of Nike's sports watches that monitor activities can be considered more of a real smart-watch than anyone currently in development at these various tech giants.
So, there you have it. Watches for everyone coming to a Holiday season near you.