What's it about?
Sci-Fi exploration/survival game with MMO-lite features. They have a large number of systems(18 quintillion, apparently) and each of these systems is procedurally generated. Which is usually code phrase for 'boring, bland, unorginal' buuuutt... I've been following closely and I was sort of caught off-guard by how plausible some of the procedurally generated planets/systems are, some of them are quite imaginative and I started to like the game. I haven't actually played it, but I do know the basics - while it's a great big sandbox you share with other players, the entire point of the game is to survive and make it to the center of the universe - you do this by collecting resources, upgrading your ship, suit, etc. Naturally it's not as easy as it sounds, but the other big draw for me is how it's all seamless transition from space to atmosphere and back.
I'd link a few videos or even the announcement link, but I can't until I'm approved. Polygon has a few good articles or even GameInformer has a pretty well rounded preview of the game. I'm sure a lot of other sites do as well, just two I frequent.