I'm amazed there isn't a Cyberpunk 2077 thread already, it reeks of heresy to be honest.
Night City, California. Year 2077.
The world is broken. MegaCorps manage every aspect of life from the top floors of their sky-scraping fortresses. Down below, the streets are run by drug pushing gangs, tech hustlers, and illegal braindance slingers. The in-between is where decadence, sex and pop culture mix with violent crime, extreme poverty and the unattainable promise of the American Dream.
You are V, a cyberpunk. In a world of cyberenhanced street warriors, tech-savvy netrunners and corporate life-hackers, today is your first step to becoming an urban legend.
So in case you've been living in a cave for the last couple of years, CD Projekt Red - the developers of the Witcher games - are working on a game called Cyberpunk 2077 which will be set in the Cyberpunk universe which I believe is a pen-and-paper (or boardgame?) roleplaying game. I am really looking forward to this game since the Witcher 3 was easily the best RPG game I've ever played.
The very first reveal was back in October 2012.
Then there came a cinematic trailer in January 2013. I'd recommend watching this breakdown of the cinematic trailer so you can get an understanding of the universe.
And now there is an official E3 trailer.
Here are some screenshots of the E3 trailer from the cyberpunk website