Not only are computer screens getting bigger, they're also finally getting better — which might be more important. In June 2012, Apple introduced the first mainstream computer with a high-definition screen: the MacBook Pro with a resolution of 2880×1800 on a 15-inch display. This screen delivers a pixel density of 220 PPI (pixels per inch, corresponding to the DPI — dots per inch — that measure laser printer quality.)
Apple uses the propaganda term "Retina display" for screen qualities above approximately 200 PPI, under the theory that this is as much as the human eye can resolve. Of course, this is not true: we need around 900 PPI for a screen so good that adding pixels wouldn't make it look any better.
Although Apple's screen quality isn't perfect, it's dramatically better than anything on offer from other computer vendors. It's a disgrace that the PC industry hasn't recognizably improved screen quality over the last decade — despite the fact that we have known for decades that 300 PPI screens offer dramatically faster reading speed than low-density monitors.
By all means read his whole post. I'm bringing up the subject now because last week I bought myself a MacBook Pro 15"—and it's been a revelation. No doubt 300 PPI would be even better, but until it comes along I'm more than content.
Composing text on screen has become a pleasure, and reading is too—whether or not I'm reading any faster. Most strikingly, this machine has made me realize how god-awful tiring it's been, for years, to read and write on a low-res screen.
So we finally have something like the resolution that Nielsen has been demanding for decades. As HD screens become the norm, they're going to oblige web designers and writers to reconsider content and display issues: Can we write longer sentences in longer paragraphs? I suspect we can and will. Should we prefer serif to sans serif? Nielsen thinks it's now a personal call, based on branding or the "mood" of a given type style. I agree.