As part of its upcoming "Discovery 2.0" update to Steam, Valve is asking developers to use more screenshots that show off the actual game, instead of concept art or stills that may not be representative of the final product.
The news comes from an update addressing Steamworks developers, later shown to Polygon. In the update, Valve outlines two requests for action it seeks from developers: the first, to tag any screenshots a developer felt were "inappropriate" to better filter them out of the Steam pages of users who would prefer not to see offensive content.
The second request asked developers to upload fewer images of concept art or stills from trailers for their games' store page, and more shots of the games in action. "When the 'screenshot' section of a store page is used for images other than screenshots that depict the game," wrote Valve UI designer Alden Kroll in the update, "it can make it harder for customers to understand what the product is that they are looking at."
Valve cited a game of their own, Dota 2, as a major culprit. The game's store page previously featured concept art for the game's characters instead of actual in-game shots. Currently, the page features more in-game shots, showcasing characters using the in-game character viewer instead.
According to the update, the Discovery 2.0 update, "is still a couple weeks away from going live."
The first culprit for the change in policy is likely No Man's Sky (which currently has a lawsuit against it in the UK for false advertising), but it's not alone. Lots of games have concept art on their pages (like Dota 2), and it can alter players' expectations of the game. No matter what caused it, this is a good change to see.