With Uncharted 2 out and scarfing up a bathtub of major awards, especially for visuals, the games' creators are showing us how it was built. Several Naughty Dog artists have posted a ton of art in this thread.
Richard Diamant, ND's lead character artist, was joined by Darcy Korch, Bryan Wynia, Nichol Norman, Behrooz Roozbeh and many others showcasing their work in Zbrush's community forums. You can get a look at the wireframes, textures, environments, matcaps, and, of course, character models forming the source material for this game.
The thread began with Diamant posting some samples, and then his colleagues quickly followed with theirs, to the delight of forum readers. And now, you. Great community outreach by Naughty Dog, even if it wasn't the intent.
Clarification: Calling these assets concepts is inaccurate. Most if not all were actually used for the game or the public promotion of it.