Hmm, I guess BioShock, Braid, Ico, Shadow of the Colossus qualif if you take into consideration the overall agem (not jsut teh art style, but the story, the emotions meant to be expressed throught the game etc.).

I'm not sure any game yet has really been a work of art, however four I'd consider as having come damn close, close enough to be argued as possibly works of art, are ICO, Flower, Shadow of the Colossus and Silent Hill 2.

Everything else has artistic direction but only as craftwork to design the game, not as art as its own right, or is simply a derrivative narrative or mix of elements with no clear theme.

Of course, I haven't played every game ever, but out of those I have those are the only four that felt close.

Flower - Visual art.

MGS 4 - Acting and direction art.

My opinion of course.

This.

erm, limbo

There is a startling lack of Portal in this thread.

Every game in existence is art. The definition of art is very loose, or abstract. Pretty much anything we have a hand in creating can be considered art. You might not think of it as art, but it is in someones eyes. Every car built is a piece of art, every fork, every door. What exactly is art? How are you defining art? I'm not trying to start an argument or flame war. It's just hard to categorize a few games as "art" in such a broad sense. Art is commonly associated with what the masses refer to as fine art. Paintings, sculptures, sketches, etc. The dictionary definition says pretty much what I stated in the beggining. To participate in the thread, and not be such a pompus ass.... My favorite games art-wise, in no particular order are Bioshock, Final Fantasy X, God of War 3, Patapon, Mad World, Street Fighter 4, Valkyria Chronicles

To me games contain art (backgrounds, characters design, music) or are designed to make art (Wii Music, Mario Paint) but are not art in themselves.

This assumes that games are not art, and that art is defined by a lack of utility.

Though leaving that overtread debate aside, i'll go with Kirby's Epic Yarn.