Some games are an overtly artistic statement (Journey), others are more similar to a good theater production (Planescape:Torment). Still others are an escape into imagination and other worlds, similar to a novel (Morrowind). I think all of the above qualify as art.
Does a cheap action movie or bodice-ripper novel qualify as art? How about a derivative FPS or Leisure Suit Larry? Ducks on velvet or caricature bought from an artist on the street? All creative endevors can produce works that qualify as great art. All can just as easily churn out complete rubbish. It's all relative.