Here are features unique to Series 6:
1. U1 Ultrawide band chip (for tracking physical position of iPhone 11 and on, as well as the forth coming AirTag tracking devices.)
AFAIK, this chip is not being used yet. Curious to see the applications when they come. Maybe *that* will change my mind at that time.
2. S6 processor with 20% faster speeds.
OK. Fair.
3. 5ghz wi-fi.
That's a nice one. For me though, the watch is unfortunately not the only device that I have that doesn't support it, so it won't help at this time. If it was, I would - maybe - upgrade just to get rid of my 2.4GHz wifi!
4. Always on altimeter.
No use for me but I can see how that'd be useful.
5. 2.5x brighter always on screen when outdoors (I bet it is the same screen but battery changes and processor power savings on the S6 chip likely allow it to be brighter without losing all day battery life).
I have honestly never, ever, felt like it wasn't bright enough
6. Blood Oxygen sensor.
So that one is interesting. Or it would be if it was always-on, with history and alerts, like the HRM. I didn't see that it was when I watched the video, admittedly with only one eye. Seemed more like the ECG, an app that you have to fire up when you want to perform the check?
7. The new faces shown at the event are unique to the S6 (silly I know) based on the WatchOS 7 GM released today not having them.
Hmmm.
8. 20% faster charging. (I bet it doesn't actually have something that makes it charge faster instead maybe it sips power compared to the S5 chip allowing it to use a smaller battery that takes less time to charge? i'm sure a teardown will reveal all soon.)
That one is great. I could use that.
This update is a great update because it represents the final polish on the Series 4 generation of design in my opinion, just like the Series 3 was the pinnacle of the first Apple Watch generation. I fully expect a significant update next year with case changes (it will still be square! always!) and other large new features as the NEXT generation of Apple Watch starts in 2021.