I prefer 16:9 too (for tablets, which is the topic of this story) but for a completely different reason: it is easier for someone with large hands such as myself to pick one up from a flat surface with one hand (in a "beer can" grip).
(For laptops and desktops, I prefer 4:3 as long as I have at least 1280 pixels of horizontal resolution.)
I generally favor 16:9 for phones, 16:10 for compact tablets (e.g. Nexus 7), 3:2 for large tablets and small laptops, and 4:3 for midsize-to-large laptops and desktops.
- Devices meant to be used in one hand should have aspect ratios that minimize width in portrait mode for ergonomic reasons.
- Laptops become very unwieldy past a certain width. From personal experience, a 14" 4:3 laptop is as wide as I'd ever want to deal with. 12" and below can be 3:2, though.
- Tablets should shoot for something in between, in part because they're used for media that varies wildly from 4:3 magazines to 16:9 movies to everything in between. I'm slightly biased here because I love reading comic books on tablets, those are naturally 3:2, and from personal experience my Surface Pro 3 is perfect for that purpose. 16:10 is a nice compromise for tablets that are small enough that holding it in one hand is still feasible (I speak from personal experience with a 2012 Nexus 7).
- Desktop monitors should maximize space in all directions. Square would be ideal, but I don't think anyone has ever made square monitors in significant volumes, so I just say 4:3 instead.
Actually, I have to admit that I'd probably prefer a square screen for desktops, but I don't think square monitors have ever been made in significant numbers.
(For laptops and desktops, I prefer 4:3 as long as I have at least 1280 pixels of horizontal resolution.)