The Nintendo Switch's OS and features continue to evolve with the latest firmware update, version 4.0.0. The standout feature is video capture; by holding down the capture button you can seamlessly record 30 second clips of gameplay. You can even edit and cut them later, and post them online via Twitter or Facebook. I predict a huge upswing in disastrous Breath of the Wild gifs, and a resurgence of Luigi's Mario Kart 8 death stare.
The update also, finally, lets you transfer save data and player profiles to another system. Naturally this wipes all profile data, eShop purchases and save data from the previous Switch and moves it over to the new console, but it's a badly needed feature. If your Switch gets broken or bricked, or you and a significant other have been fighting over a single console until you could afford to buy another one, you can now preserve and transfer everything from your old Switch without having to send it away to a Nintendo repair center.
Full update details are here, and the trailer below details the video capture features.