Buy Cyberpunk 2077 on Steam and you get an exclusive short story
But if you buy it on GOG you get an exclusive comic.

Anyone who buys Cyberpunk 2077 on Steam, whether as a pre-order or after release, will receive an exclusive short story called '2AM — She Calls'. To be clear, this is not an in-game reward. It's a story written by Cyberpunk 2077 story lead Tomasz Marchewka that will presumably show up as a pdf in your game files. As explained on Twitter, the story "will show you the hostile streets of Night City as seen by Frank, an ex-ND officer working the night shift as a Combat Cab driver." Buying Cyberpunk 2077 on Steam will also net you some other exclusives, "including avatars, posters, and a wallpaper", presumably for display on your Steam profile.
It's unusual for Cyberpunk 2077: Big City Dreams, a 50-page digital comic about scavengers in Night City written by CDPR's narrative manager Bartosz Sztybor, with art by Filipe Andrade and Alessio Fioriniello.
Note that this is different to the some of the The Witcher ones were quite good.
So yeah, buy it from Steam if you like stories without pictures and from GOG if you like stories with pictures. At least they're not in-game exclusives?
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Jody's first computer was a Commodore 64, so he re having to use a code wheel to play Pool of Radiance. A former music journalist who interviewed everyone from Giorgio Moroder to Trent Reznor, Jody also co-hosted Australia's first radio show about videogames, how weird Lost Ark can get. Jody edited PC Gamer Indie from 2017 to 2018, and he eventually lived up to his promise to play every Warhammer videogame.