"Team Fortress was sort of the obvious choice for this," Ludwig said. "The Team Fortress community is large and healthy. There are millions of people playing TF every week, but they're also used to us shipping a lot of updates." Team Fortress 2 receives updates nearly on a weekly basis, but it's not uncommon for players to see multiple updates to the free-to-play shooter in one week.
Ludwig said Valve is currently experimenting with VR in its other games, but is hardly committing to anything beyond testing at this point. "We've played a bit in Left 4 Dead; we've played a bit in Half-Life 2. We haven't taken any of those other games to the point where they're anywhere close to being ready to be shipped; we've just sort of experimented with head tracking a little bit."
Valve chose to partner with Oculus as opposed to creating its own display simply because it made more sense to go that way – the two companies each had something the other wanted. "We've done a bunch of experiments with various bits of hardware, but we don't have a display that we can ship. Oculus is actually out there doing this, and so we're partnering with them because they have the hardware and we have the software and we can help each other out. And we can both learn a lot in the process."
"We don't know how strongly people will react to VR," Ludwig concluded. "We don't know how popular it will be, what people wanna see. It might be that we need to learn a lot more from TF before we move on to other titles. We just don't know what's gonna happen."