I really don't like Epic personally, but this is still pretty huge. Linux and SteamOS have come a long way. CEO Tim Sweeney has always been very negative towards the idea of Linux support, so Epic changing that stance would suggest that Linux/SteamOS has finally become too big of a market to ignore.
Damn, how the turn tables. I remember reading somewhere how Tim boy expressed that Linux was "terrifically hard audience to serve due to fragmentation and anticheat concerns”. I also remember thinking “you’ll come around when the money looks good, bitch”. He did.