Via Twitter:
After 13 years, GameTrailers is closing down today. Thank you for your continued support over the years. It has been an adventure.
— GameTrailers (@GameTrailers) February 9, 2016
If the tweet doesn't work, here's their Twitter page: https://twitter.com/GameTrailers
Their last livestream, today at 6PM PT: http://www.twitch.tv/GameTrailers
Employees got notified just a few hours ago: http://www.neogaf.com/forum/showpost.php?p=194642343&postcount=6727
:'(