Valve has quietly entered the streaming market with the beta rollout of Steam Cloud Play. The service introduces GeForce Now streaming integration, but may include other services in the future. For now, publishers can opt into GeForce Now streaming for their games through the Steam backend. The service also promises to let users launch GeForce Now streaming through Steam for supported games. As of now, only a limited number of games will be supported, and users will need to download the GeForce Now client and then connect their Steam accounts to it, like they already do.
On the official page it states "Customers will continue to acquire games on Steam the same way they do today, and partner payouts will remain the same". It looks like Valve seems to be helping Nvidia explain what GeForce Now is and isn't, and how it affects Steam publishers, which could be a big help for GeForce Now. A variety of Steam games are already playable through GeForce Now, but with the service lacking in audience members, multiple developers and publishers have requested that their games be removed. Now with the ability for publishers to opt-in by flipping a switch on Steam, Nvidia's library of supported games should have an easier time growing.
This looks to be the just the start of Steam's cloud features, with valve saying "continue to build features and server capacity for players," and when developers opt into GeForce Now, they are also opting into cloud streaming "hosted by Valve," suggesting that the company may have plans for its own cloud streaming service. Valve has already built technology for livestreaming, Remote Play, and Remote Play Together, so it's not much of a stretch to imagine Valve building its own cloud streaming service.
Steam integration is part of a larger change to GeForce Now, with the service moving to a new opt-in model across the board. This gives developers and publishers direct control over whether their games are accessible through the service. Valve may also be feeling a little pressure from the Epic Games Store on this front: In early March, Epic Games CEO Tim Sweeney said that Epic will "wholeheartedly" support GeForce Now, for its own games and "Epic Games Store titles that choose to participate (including exclusives)."