I've been a Mac-only user for about 15 years now, and I'm teetering on the edge of abandoning the platform. A lot of technically-minded people I know are considering the same. The hardware is outdated, underperforming, and overpriced - and what's worse is Macs are now <i>completely</i> user-unservicable. So I'm weary when I read about an OS update nowadays (it used to be I was excited), because OS X has been getting slower and more tedious to work with for a long time now.<p>Metal: it's good that Metal exists, even though Apple has no ambitions to introduce performant or even recent graphics adapters into its PC products. Some people may even have wished for Metal adoption beyond Apple, but that's not happening. What's conspicuously missing from Sierra is Vulkan support, so gaming on the Mac is basically a prohibitively walled garden that can only be tackled economically by the big graphics engines (which have mostly ignored the platform) and pre-existing iOS developers.<p>Swift 3 and Apple Pay: this should not be an OS feature, or at least one that is featured as spots #2 and #3 on the bullet point list.<p>Picture in picture: in a better world, this would be a window management feature, but OS X is reducing its windowing capabilities in anticipation of a full merge with iOS, it seems. So this is going to be a specialized video component feature instead. Even on the screenshot they chose to show this off with, it's clear this is drastically worse than just lining up non-fullscreen windows side-by-side.