"Steam has already dabbled in selling non-game software and movies, as well as soundtracks bundled as DLC, but up till now these categories have played second string to games. The mock-up, which you can see above, integrates them into the main nav where we'd normally see 'Library,' and introduces comics and TV as major new categories.
The inclusion of Halo 5: Guardians in the games list on the left (enlarge the image above to see) speaks to how much of a placeholder this image is. Some of the game icon choices, like the now-defunct Evolve and eight-year-old Mirror's Edge, are also strange, further suggesting this is just an artist's vision."
Read more by clicking the link in the tweet....