**sigh**
Games are already art. To create a game, you need many, many digital artists to create the characters, scenery, levels, music, writing, etc.
Imagining something and then creating a picture of it IS the work of an artist.
Writing scripts and music is the work of artists.
Sculpting three dimensional moving sculptures of the characters is the work of an artist.
"Painting" the beautiful skyboxes that make the world seem real is the work of an artist.
For a medium that combines the skills of sculpting, film, writing, and musical composition - four major realms of artistic expression - how can games not be viewed as art?
Then again, there's good art and bad art. A lot of time, when people say "art" they are only thinking of good art, not all art.
Garfield comics are art - someone drew them and wrote dialogue. It might be a crappy drawing and a sucky script, but it is still art - bad art. (or good, as Garfield has good days and bad days).
A crappy novel is still art, even though it's crappy.
A bad painting is still art, even though it's bad.
A fricken macaroni sculpture made by a kindergartener is technically art.
Amateur porn is art.
Pixar movies are art (good art typically - I bring them up because they're created by the same type of 3D programmers and animators who create video games).
Oh, and as far as the "games are interactive so they aren't art" argument... so are fucking novels. When you read a novel, you, the reader, have to contribute mental images of the characters and the locations. The author can aid you with good description, but that description can only do so much - eventually the process becomes interactive between the book and the reader.
Hell, much of recent post-modern art (ie art installations) are interactive in some way. Making art an interactive process is THE recent trend in the art community. So not only is the interactivity =/= not art argument stupid, it is blatantly not true.
Here's the trick - art is made by artists. Sculpture is made by sculptors. Music is written by composers. Etc.
Games are written by writers, sculpted by 3D artists, brought to life by animators, set in a world created by other digital artists, and provided with a score composed by composers.
Games aren't just art - they're one of the greatest artistic forms known to man. No other form of art combines so many different artistic disciplines into one art form.
tl;dr: Games are not only indisputably art, they are in fact the most complex art known to man.
... other than Pixar films.