For me, the heart rate monitor is like the feature unique to the iPhone 6+: the barometer. It sounds really cool and on the first day it's the best thing ever. Then you stop caring and never use it again. I don't go to the gym. I'm never going to the gym. There's an awful lot of time and money and weight and space put into the AW to provide a heart rate monitor. How many people are going to use it regularly. Be honest! Because a lot of people are talking about waiting till the second generation or even the third. But will Apple add genuinely useful new features, or will it stuff that sounds cool but ultimately really doesn't make that much difference, day-to-day?