Ars & Co seems to be convinced that HiDPI elements means HiDPI Macbooks
Here’s my challenge: Plug your Macbook Air into a Cinema display or some other hi-resolution external and see how much faster your battery drains.
This isn’t going from 480x320 to 960x640 as it was with the iPhone. The iPhone still doesn’t break the megapixel barrier. Double the resolution means quadruple the number of pixels. (Gruber pointed this out shortly after the iPhone release) long ago. That’s a HUGE impact on graphics performance, especially for mobile and integrated chipsets. You’re talking about going from 1 megapixel (1366x768) to 4.1 megapixels (doubling the resolution), not from 1 to 2 megapixels. Whether or not the physical size of the content changes, you are still driving all those pixels, and the scaling is going to happen either in software or at the GPU level, not in the display.
I think HiDPI is great for Large-Screen-Large-Distance operations, and I think its great for the accessibility implications, but I don’t think we’re going to see a Macbook Pro with a 4K display shipping anytime soon. This might be posturing for the eventuality, but I don’t think its as direct of a correlation as others are making it out to be.
That said, I’ll happily eat these words if they do manage it.