Definitely a gimmick at the moment - smartwatch hardware isn't very compelling yet; it's simply not possible to build a color touchscreen smartwatch with the sort of form factor + battery life that would make it appealing to the average consumer. (even the best-looking Android Wear watch so far, the Motorola 360, has that ugly chunk cut out of the bottom of its screen not to mention highly questionable battery life) So right now I look at the whole sector pretty much the same way I look at Google Glass - might be fun to build something for it if it catches on, but that's a while away from happening if it ever does.
If any sort of wearable is going to break through in the next year or two, it'll likely look and function more like a fitness band - minimal interactivity, just enabling you to do interesting things with your phone that you couldn't do otherwise. A theory I share with a lot of other observers is that the upcoming Apple iWatch, if it exists at all, will essentially look like a Nike FuelBand with more sensors + a fingerprint scanner button that can be used for authentication and voice commands.