The PC Portal 2 ARG was the biggest waste of spacetime/money I've ever been suckered into. They didn't even execute it correctly as there were potatoes left over when the game was released.
I won't be actively taking part in another Valve ARG.
They want to throw out some hints that's fine.
Now onto the game:
I hate to dredge it up; but as good as Portal 2 was it was only half as good as it could have been because it was consolized. Tiny map slices and no demands made on mouse/keyboard users took much of the excitement out of the gameplay.
If HL3 has these problems even I will consider PC gaming dead. I'll just take up Eagle Dynamics flight sims- finally having time for them since there won't be anything else to play.