I agree with you about watches. Tablets though, I disagree. I have several different tablets and they do different things in my workflow from my laptops or phones. My tablets can be an ebook reader, weather center, and video viewer. One of them, I read comic books on. They're easier to use for those purposes than my laptop. I would need a second monitor to do those things, and I would need to switch it to tate mode for comic books and other ebooks to be comfortable for me to read. Plus, I couldn't read easily in bed or somewhere like that even with the form factor of the smallest netbook in my collection.
I mean that I have two different radar apps along with the Accuweather software. I look at it both for long-term and short-term forecasts. The last time I had a dedicated device just to do weather with the granularity and scale that I have on my tablet, the unit was called a home weather center (and required both GPS and internet access).