Well, that's pretty neat I suppose. A sort of cloud save for games would be a nice feature in the future as well.

You should update the OP with the full changelog

Improvements Included in Version 4.0.0 (Distributed 10/18/2017)

Added the following system functionality

• Capture video on select games
  • To capture video, hold down the Capture Button during gameplay
  • Up to a maximum of the previous 30 seconds will be saved in the Album. You can trim the beginning and end of each clip, and post to Facebook and Twitter.
  • As of October 18th, 2017, this feature is compatible with The Legend of Zelda: Breath of the Wild, Mario Kart 8 Deluxe, ARMS, and Splatoon 2
• Select from 12 new Super Mario Odyssey and The Legend of Zelda: Breath of the Wild icons for your user
  • To edit your user icon, head to your My Page on the top left of the Home Menu > Profile
• Transfer user and save data to another system
  • To transfer, head to System Settings > Users > Transfer Your User and Save Data
• Pre-purchase option on Nintendo eShop
  • A pre-purchase option will be available for certain games. This option allows pre-load of the game to your system for quicker play when the game is released.
  • This feature will be supported by future game releases
• News channel updates
  • The news feed has been updated with a new look.
  • Unfollowing a channel will remove that channel's content from the news feed and following the channel again will make it reappear.
• Match software version with a group of local users
  • To create a group, head to the software's Options > Software Update > Match Version with Local Users
  • Everyone's software will be updated to match the most recent version in the group
  • All users must be on system menu version 4.0.0 or later to view and join a group

General system stability improvements to enhance the user's experience, including:

• Changed the specification which hid wireless networks using TKIP security from the network search results. Wireless networks using TKIP security will now display in search results as a grayed-out selection instead of not being displayed
  • The Nintendo Switch console supports WEP, WPA-PSK(AES), and WPA2-PSK(AES). If your router is using a different security type (e.g. WPA-PSK(TKIP)), you will need to change this security type within your router's settings.

http://en-americas-support.nintendo.com/app/answers/detail/a_id/22525/~/nintendo-switch-system-updates-and-change-history

Eh....It's something. Not much, but it's a bold step towards perhaps thinking about possibly maybe taking off the data/account management monkey hat and joining the human race.

A step in the right direction.

30 second limit is not great,could be because of limited storage?

So we now have a way to filter out games on sale and transfer save files.
Slow but steady but mostly slow, that should be the Switch slogan.

Not long now until Switch's feature set can join Gen 7 consoles.

It could be better and I wish it were for all games. Maybe in the next update, I hope. But even on PS4 and Xbox One, my video saves are relatively small.

Saw on reddit that 4.0 also adds USB wireless headphone support.

Mother of God.

Support for wireless USB heasets got added as well:

Switch version 4.0.0 adds support for wireless USB headsets