What I want is as many vertical pixels as possible; this is the first new screen I've seen that's got more than my 10-year-old CRT (1536).
(At this point some wag is going to suggest portrait mode, but I've never seen a laptop with a portrait screen that can be used at the same time as the keyboard).
Because there's no space / it would be too small. We're talking about sub-15" display here. So while wide display is great in 22"+, it sucks for everything (except movies maybe) on smaller devices.
I don't especially want a single tall, thin window for code. 5:4 is still wider than it is tall. My usual development environment is Emacs with two panes (Emacs calls them windows for historical reasons) side by side on 4:3.
My thinking is that a screen that's close to square works better for a wider range of tasks than one that's very oblong. A rotating oblong screen that could be tall or wide might work nicely for a lot of situations too, but it would be hard to implement well on a laptop.
