In context: The Steam Deck is going to have an impact on the PC industry. Even those who don't buy one will see its effects, especially if they use Steam's Big Picture mode, which is being replaced by the handheld's user interface. Now, we've got our first glimpse of what it will look like.
The shots come courtesy of Pavel Djundik (via PC Gamer), a name you may recognize as the creator of SteamDB. He tweeted that an image of SteamOS 3 leaked, and people are already getting it running on other portable consoles such as the GPD Win 3 and the Aya Neo.
Steam Deck UI, it's basically the desktop library just reformatted a bit.--- Pavel Djundik (@thexpaw) September 15, 2021
There is no way to access the store at the moment. pic.twitter.com/mI2dgAPpck
Djundik notes that the images he posted were actually taken on Windows, not the Steam Deck hardware. He does add this is a work-in-progress that originates from the dev kits Valve sent out recently, so there may be some changes in the final version.
Speaking of the dev kits, Valve did say the "engineering verification test builds" are functionally identical to the commercial versions coming at the end of the year.
Back in July, a moderator on the Steam community forums wrote: "Yes, we are replacing Big Picture with the new UI from Deck. We don't have an ETA to share yet though."
Replacing the little-loved Big Picture mode will be welcomed by most Steam users. Announced in 2011 and released in beta 2012, it is designed to give PCs a console-like UI with controller support when connecting to a large TV. The mode hasn't been given a significant refresh since way back in 2015.
The first shipments of the Steam Deck are scheduled to begin in December 2021, but the huge demand has seen Valve change the availability for new pre-orders---most people aren't going to get their handhelds until later next year. The good news is that eBay appears to have carried out its promise to remove Steam Deck pre-orders from the auction site; its policy states that all pre-sales items must ship within 30 days.