There's a reason Xbox One comes in that whopping great 1980s VCR style case, and it's not because some one in authority at Microsoft went mad. It's for cooling, to help keep it quiet and reliable, and so you can leave it switched on constantly for the next ten years.
According to Digital Foundry, which spoke to an unnamed Microsoft staff member, the final console ought to be entirely silent while in standby mode and when running media and dashboard applications, with the cooling fans only kicking in when the AMD core is being seriously taxed by multiple oil barrels and crates exploding as players make their way through whatever war-based FPS takes their fancy.
The idea is to Make Xbox One a games machine that's as robust as your digital TV box, one that's also quiet enough -- and quick to boot from a saved memory state -- that you'd never really want to turn it off at the wall. Not unless you have some sort of OCD fear about things catching fire while you sleep. [Digital Foundry]