If you haven’t heard, Hawaii is sunny. (Except when it’s raining, but wait a little while and that’ll pass.) I spent the better part of the week walking around in bright sunlight wearing sunglasses. At home I noticed that the Series 2 Apple Watch was brighter (Apple says twice as bright!) as my original Apple Watch, but the real validation came when I was on vacation: Despite my sunglasses and the bright light, I never had a problem reading my Apple Watch at any point. That’s not something I could say about the original Apple Watch.
I've never written about the Apple Watch Series 2, mainly because its banner features (fitness, etc) aren't anything very compelling to me or relevant to my life. (The performance gains are admittedly nice, but watchOS 3 has greatly improved the experience on my Series 0 model, so I don't feel like I'm missing that much.) That said, I have wondered what the Series 2's brighter screen is like from an accessibility standpoint. My Series 0 is difficult to read in bright sunshine, and it'd be interesting to compare the two. By Jason's account, the difference is dramatic.