A number of sources, including those who informed me of the Switch's design and detachable controllers back in July, have all confirmed other capabilities which Nintendo is currently keeping quiet.
Let's start with the Nintendo Switch's screen. It is 6.2" in size, 720p and - for the first time in any Nintendo device - boasts a capacitive multi-touch screen.
(Both 3DS and Wii U featured resistive touchscreens, reliant on pressure and less precise. They were also single-touch only.)
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So, how will the touchscreen work when the Switch is docked? While connected to your TV the Switch itself is out of reach - you play either with both JoyCon controllers attached to the system's grip or with a Pro Controller. The Switch's touchscreen is almost entirely obscured within the console's dock.
The answer may lie hidden in the right-hand JoyCon, which houses a short-range IR sensor in its base. This could be used to point at the TV to replicate basic touchscreen functionality, picked up by a corresponding IR sensor in the Switch's dock.