Its just a code name, every big company does this just in case of a leak like this, half-life 3 was in development for a long time im sure of it.
First of all im pretty sure valve does not like the idea of episodic content for half-life anymore, EP3 is gone along with EP4 for good, they wanted to build a new engine (Source 2 and is confirmed) because source is already outdated when EP2 came out, they will not show HL3 on an old engine that's for damn sure.
Also notice how hl3 art gets leaked yet none do so far l4d3
Gaben was onced asked when is recochet 2 coming out as a joke refering to hl3 and he responded with pretty much, its being worked on, we just dont talk about it because we keep changing our minds about story.
http://www.youtube.com/watch?v=TS9zD_LPhw0
"everyone that worked on ricochet 2 (aka hl3) continues to work on ricochet 2"
heres another tease of Gaben forging a crowbar saying these things take time
http://www.youtube.com/watch?v=fTsR4RBH000
Why did valve not develop blue shift and opposing force? thats because when they finished half-life they started working on half-life 2 right away, so they hired gearbox to develop the games while valve works on source and half-life 2.
does this seem familiar? csgo? why didnt valve develop csgo? i suspect that they have their hands very full at this time, developing dota 2 which is now at full release, source 2, and HL3
why did i make this thread? mainly to try to silence all the people who are saying "BUT VALVE DOESNT CARE ABOUT HL3 ANYMORE!" but also to try and start a discussion on if you agree with me or not? do you think l4d3 is a mask for hl3? or do you think l4d3 is indeed in the works as a standalone or a mutliplayer component to hl3 similar to what cs:s was to hl2?
Valve is not going to show a source 2 tech demo without showing a game afterwards.