bansama: No, that's for all games, not just Valve ones.
Do you have any
official statement on that, I mean something really official, not some moderator saying that he "think" that it "might" cover all games.
The authentication servers do not make any distinction between who published the game, they merely check that your account is authorised to play it. So, EA, Ubisoft and all other publishers using Steam have no say in the matter.
That's not what even Valve said, they said that for each games the editor was allowed to decide the protection scheme used of his games, whenever the authorisation was checked only after purchase, everytime you try to play the game or even after a certain playtime.. so it the authentication servers can have an "a la carte" protection scheme I hardly see how it would be impossible to only unlock some games and not the others.
bansama: Feel free to have that confirmed for you on the Steam forums if you don't want to take my word for it. Afterall, the question gets asked on an almost daily basis now over there anyhow =)
The question get's often asked on the forum but I never saw any official answer for it, usualy the thread in questions either are locked or get's lost . And I also tried three times by e-mail and never got any answer either.