In a post on the Bohemia Interactive website the developer has announced that, after some deliberation, ARMA 3 will only see release on Steam. The decision was made based on the extra features that Steam can offer, the benefits that players will enjoy and also the effect that piracy has had on sales.
"We have evaluated the pros and cons," said the impressively-named Joris-Jan van ‘t Land, project lead, "but in the end Steam enables us to release Arma 3, brings massive advantages to the game, and improves the end-user experience."
It's a logical decision for several reasons. Obviously Steam already has a tremendous reach already and, as van ‘t Land adds, "the majority of our players already come from Steam." A Steam-only release allows all these players to keep their games up to date and, as van 't Land's post acknowledged, ARMA games have frequently required regular tweaks and updates. Steam's delta patching means much smaller, faster updates, rather than gigabytes of downloads.
He also cited Steamworks as an asset, as it "offers a library of features which we can fairly quickly hook into Arma 3," said Bohemia were considering how best to support dedicated servers and their admins and also added that one of Bohemia's priorities was "User Generated Content and multiplayer."
The post paints a picture of a challenging development and concludes by saying that, if the game couldn't be released on Steam in this way, "There was a very real chance there would be no Arma 3 this year otherwise."
ARMA 3 is set in 2030 and pitches the forces of NATO against armies led by Iran. It has a damn impressive game engine with a gorgeous day/night cycle, HDR implementation and underwater lighting effects, producing in-game screenshots that look like this: