That sadly does not mean much, because he basically did not deny anything that was said, just saying someone is trolling doesn't mean that half life is an important project, so things are somewhat unchanged. 1% extra hope to see Half Life 3, that's all there is to it.
I found this on reddit : http://www.reddit.com/r/Games/comments/3ei2be/halflife_3_will_never_release_heres_why/
link to the video in the thread:
I apologize for bringing up a rumor, but the arguments made by these guys are solid in my honest opinion, and while they have been wrong about things...