Half-Life 2: Episode One is now due out on May 31st according to Valve, although it'll still launch simultaneously on Steam and at retail, priced $19.99.
Speaking to Game Informer at GDC last week, marketing director Doug Lombardi confirmed the slip - Valve had previously been targeting an April 24th launch.
Meanwhile, in an interview that also touched on digital distribution plans and Valve's future plans, founder and MD Gabe Newell said that it took him "seven hours" to play through the episode recently. "There's a lot of variability of how long it takes people to play," however.
Newell also offered a glimpse of what players can expect from the story, which picks up at the end of Half-Life 2. Now, this is probably redundant, but if you haven't finished Half-Life 2 yet you'll want to skip the next quote...
"Youre on top of an exploding building, okay, so how do you not all die. It answers a bunch of those questions. It also raises some questions about what the G-Mans real role is in the Half-Life universe, so there are some surprises there for people," said Newell.
The Valve man also talked a bit about Steam and how digital distribution and free weekends, like the one used to promote Day of Defeat: Source recently, have gone over, and revealed more of the latter are planned. Furthermore, friend trials allow you to show stuff to your online chums - something we've also seen with NCsoft's MMORPGs like City of Heroes in Europe.
"If you bought a copy of one of our games you can give five trials to your friends. You type in your e-mail address and then youll see the first time that they play youll have this little screen where you can say, 'Oh look, hes playing. Oh, he hasnt played yet so Im going to delete him and replace him with somebody else.' And give your friends a chance to play."
Newell believes strongly in digital distribution, as you might imagine, but added that he was cautious about how Valve uses it.
"I think you have to be careful. Digital distribution is not a portal. Its not a different way for people to be a publisher. Its tools for developers to connect with their audience," he said, adding, "I would be really surprised if, twelve months from now, any title doesnt have some form of digital distribution strategy."
Half-Life 2: Episode One, formerly known as Aftermath, is the first in what Valve reckons will be a range of episodic content - with a second instalment already in development.