VR? They were also working on special mo-cap software for HL a while ago.

It's a rather significant supplement if you ask me. VR isn't just a new toy. Plus, they could be working with any number of technologies for the next HL, we don't know.

think of VR like colour. it's a pretty impressive improvement, but it doesn't really change how you play the game significantly.

It's not necessarily just a new viewing device with a few cool features. What I've heard from people involved with VR indicates that it does really change the way you have to design games. For example, a writer and game dev working on VR recently, tweeted this: "Watching people trying to force GTA V into VR is scary - I'd be puking! Retrofitting games not made for VR tends to end poorly." Another example would be some things Gabe says in an interview from a while back. Listen to about 25:40-32:30 here podcast.gameslice.com/1-gabe-newell-and-erik-johnson-from-valve