Apparently confirmed fake by Valve. Too bad. The game is never coming out.
On the topic of Half-Life 3. Am I the only one who missed the news about the big concept art leak back in June? Judging by the quality of some those images I'm gonna guess that they're genuine.
In defense of Valve, the fact that the game is taking this long makes it all the more likely that it's going to be a fully fledged Half-Life 3 as opposed to a Half-Life 2 Episode 3.
I don't know about you, but I never found the concept of episodic gaming to be all that appealing, not just because Valve utterly failed to deliver on the promise of shorter development times, I'm saying this as someone who much prefers the grandness of going to the movies as opposed to watching the latest episode of some TV show. Just compare Half-Life to Episode 1. Playing Half-Life 1 and 2 is like going on a journey, meanwhile Episodes 1 and 2 feel like two trips to the supermarket, I'm not saying that the quality has suffered in any way, but they're not exactly life-changing experiences.
I am getting quite impatient though, I hope they're just pulling our leg and actually do show it in the coming days, if they don't, there's still Metal Gear Solid 5 which may or may not be shown on the 30th. This would be a truly amazing month if both were shown.