Folks that attend GDC get the pleasure of going hands on with almost every single item that gets announced during the event. That includes VR headsets like HTC and Valve's Vive VR headset. Stuff, a website that covers, well, stuff, attended the event alongside Engadget and a number of other sites; however, Stuff said some stuff that the other sites did not.
Stuff's Tom Parsons got to go hands-on with the Vive VR, but it was after his experience that he was filled with so much hype that he accidentally said he had experienced Portal 3 in the demo (you can watch him say he played Portal 3 here).
Slow your roll, don't let the hype take over — I've got bad hype-killing news.
Other sites in attendance did not say they played Portal 3 during the headset's demo, but instead what was a Portal demo. In fact, Geoff Keighly referred to it as a "new demo set in Aperture Science." Engadget, another site to attend GDC, spoke on the demo in-depth and noted Portal 2 androids and the voice of GladOS.
Tom Parsons has come out and said that he had made the "assumption that Portal 3 was going to get an official announcement," and that was the demo he played, but has come to terms that it was possibly "nothing more than a tech demo." Parsons maintains the tinfoil hat stance and will stand by his guess that it was the opening of Portal 3.
We will see Parsons. We will see.
Catch me on Twitter @TatiMo_GZ