Dang, I felt safe getting the series 9 last year and that there wouldn't be any major features this year. The sleep apnea detection would be something that could be handy as I suspect I'm borderline. It would be nice to non-intrusively test over several months to see how I trend vs. the one night sleep tests doctors typically use.
A lot of people who live alone might not know. I think I have it but a Phillips home test was inconclusive for me. I don't really love the idea of the doctors office sleep study since I'm not really experiencing any daytime affects but having my watch keep an eye on it is a nice peace of mind.