[TeMPOraL]

Depends on how they're used. I can think of 20 ideas right now for where I'd find ubiquitous displays useful - from walls changing colors (in lieu of repainting) or even displaying images (with head tracking it becomes a single-player holodeck), through infinite whiteboards, being able to read or work on digital stuff in arbitrary locations, to subtle status displays on blended items...

Hell, I'd love to have the wall above the wardrobe display a few lines of text from a book, so I can read it while cleaning the living room, with my little kid not being able to see it (due to differences of eye level) and thus not becoming distracted from independent play (or helping in cleaning) by an active computer screen.

And that's just personal use; there's even more potential application in shared spaces, in industrial use, in healthcare, ...

But if these screens are to be controlled by corporations, sneak ads everywhere and otherwise not interoperate with each other, and with every device there is? Then I don't want that to exist.