This is the best summary I could come up with:

We didn’t previously know Sony would be streaming at 4K, and it could be a big deal no matter what that “4K” actually means.

While we haven’t yet confirmed the public beta with our contacts at Sony, several users at popular gaming forum ResetEra say they’re in, and ArashiGames says you can choose between 720p, 1080, 1440p, and 2160p (4K) resolutions, with games automatically loading your cloud saves so you can pick up and play.

While cloud saves may seem like table stakes, that hasn’t always been the case: early versions of Sony’s PlayStation Now cloud gaming service understandably had no initial way to import savegames from your PS3, for instance.

Streaming at 4K resolution helps fix that, even if you don’t have a 4K screen, as we’ve explained testing Nvidia’s GeForce Now and Google Stadia.

ArashiGames says available games include God of War: Ragnarok, Horizon Forbidden West, Fortnite, Fall Guys, Destiny 2, Returnal, Demon’s Souls, Death Stranding, Sackboy A Big Adventure, Destruction All Stars, and Fall Guys — with trials available for Resident Evil Village and Demon Slayer as well.

We do know Sony had a huge hiring push around a new vision for cloud gaming, though.

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