Atari (well, the company who now owns Atari’s trademarks) has scant information about the AtariBox. Beyond the name, we know basically nothing about it so far.
RetroN 77 is a new console from Hyperkin, which is designed to play real Atari 2600 carts, apparently through emulation via the excellent open source Stella emulator, with real controllers, using the same ports as the original, so compatible with 3rd party Atari controllers, and outputting 1080p over HDMI.
Since I know nothing about the AtariBox yet, my early excitement is for the RetroN 77, but that could easily change. Hopefully Hyperkin will do the venerable VCS justice for the HDTV Age.
My hope for the AtariBox is that it will be a retro-inspired platform that caters to indie developers who want to make games in an old school style, that look like they could have been at home in the late 70’s/early80’s, albeit not strictly constrained by the hardware limits of that time. Think what Shovel Knight was to the NES; I’d love it if AtariBox were a platform for the equivalent of such games for the Atari 2600/5200/7800/400/800/Intellivision/Colecovision era of home videogames.