The art is described as being from “circa 2008″, meaning that if they’re real, they are truly just concept drawings. However, a number of things about them — the fact that the helicopter from the end of Episode 2 turns up crashed, the arctic setting, which holds with past rumours of the game’s setting, and the fact that a Combine advisor is shown, all indicate that these could well be legit.
And hey, even if they’re fake, some of these are still quite lovely. To see the images at full resolution (along with a bunch more of ‘em), head over to ValveTime’s gallery.
It ain’t news about Half Life 2: Episode 3 (much less Half Life 3), but it’s something.