It's called multitasking. Operating systems have been doing that since windows 1.0, invented roughly in the 1980es.
Instantaneously starting something means that this particular software already resides in memory in a "sleep state", you simply wake up that task And no, you cannot do that with "all your games". Obviously at some point you run out of memory. That is why XBox One reserves 3GBytes to the system, so it can have the key softwares (Kinect2,browser,skype,os stay residoent in memory).

This is really not rocket science. You pay for every cool feature. Here, you pay with ram. And with reserved cpu and gpu compute units for these features. Watch those fps go down the drain if you do all this, once the console is really out and people actually (for whatever inexpliccable reasons) game, watch tv, skype and bing at the same time.

dude chill, it was a joke.....>_>

There is nothing inherently wrong with WiiU other than the fact it pales tech wise to PS4 and XBO. Same situation happened with Wii. You can't use vastly inferior tech in your product but want to be lumped in with the big dogs at the same time. That isn't Nintendo's strategy anyway. They are trying to carve a space for X.5 Gen consoles, for those who aren't exactly looking for more insane pixels but do want some of the other innovations that naturally come with improved hardware. Wii capitalized on the fact many were not ready to pay for 400-600 consoles and were still very content with PS2/Gamecube level stuff(because in actuallity that Gen should have lasted a bit longer as well).