Not that it ever left, but it's been a long time since the time we got releases like Team Fortress 2, Portal, and Left 4 Dead coming from Valve. During a recent presentation for the upcoming DOTA 2 themed card game Artifact
, studio-head Gabe Newell noted that "Artifact is the first of several games that are going to be coming from us."
This follows on from news from about a year ago when Valve noted that it was working on multiple new games, a few of which were fully-fledged single-player or big AAA-like experiences. "We aren't going to be talking about it today," Newell said during the Artifact presentation. Adding, "but sort of the big thing, the new arrow we have in our quiver, really, is our ability to develop hardware and software simultaneously."
Which probably means games for SteamVR and the Vive headset are coming. Gabe also added that Valve was a little jealous of Nintendo, due to its ability to design hardware, controllers, and other interfaces in conjunction with games in the Mario and Zelda franchises. "That's something that you'll see us taking advantage of subsequently."
Source: PC Gamer