To say that Valve did not handle the Half-Life franchise properly would be an understatement and with fans, all hungry for any information about the game, something like this happening on Twitch would definitely attract a lot of attention.
Just in case you did not hear about it, during a VNN Editing Livestream this week, a user by the name of CoolGuy donated a few messages to Tyler and hinted that he might have some information about the Half-Life franchise.
Despite lots of people suspecting that the user was a prankster, Tyler still allows the person to go on his steam. The user revealed that he may or may not know of some of the new fact about the game. Some fans noted that his voice sounded very familiar but the whole thing was just confusing.
It was later speculated that the voice of the person sounded like the announcer for Portal 2, Joe Michaels. We do not know if that is true or not but he did have some interesting things to say.
At this point, everybody is still speculating on whether the whole thing was a prank. If you like to know more of the story in detail, you can check out this post on Reddit.