This is a 'single task' OS, that is designed to quickly boot and load up a game from any detected media, whether it is a flash drive or a SD card.
This OS will be initially aimed at raspberry pi, but can be expanded to normal laptops and other devices. It will require a gamepad(or mouse and keyboard?),
and a free SD card reader for games distributed as "SD cards".
To ensure that games can be played in any future ARM cpu types, or a standard x86 computer, there should be a Virtual Machine like Java, or ParrotVM, etc...
Maybe it could just be a really stripped down Android OS like the OUYA. However it needs a way to access and run 'android apps' without having to install it first.
The idea, is that the process of playing a game for 'raspberry pi' should consist of 2 SD cards, one to store the game console OS, and the other one storing the game's media (much like ancient apple computers with two floppy drives). On insertions, the OS should immediately detect and check if any new media contains game file, if it does, then it can play it.
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It should also support lib-ray "SD card" video format, so you can watch open sourced movies.
It should also include 'MAME' so you can play old NES games.