Roger Ebert doesn't think video games can be art:
One obvious difference between art and games is that you can win a game. It has rules, points, objectives, and an outcome. [Kellee] Santiago might cite a immersive game without points or rules, but I would say then it ceases to be a game and becomes a representation of a story, a novel, a play, dance, a film. Those are things you cannot win; you can only experience them.
Above, Ebert is responding to Santiago's comparison of video games to visual art. Santiago, a game designer, argues that video games are already art, just art still stuck in the "cavemen scratching on the wall" phase. Ultimately, video games will evolve into something greater. Santiago's mistake is in seeing video games as primarily a visual medium, like say, Picasso's paintings, instead of a narrative one, and I think it's the reason why Ebert is having such a hard time imagining video games as art.
Ebert makes a similar mistake to the one journalism experts made when they dismissed blogs as "not journalism." Ebert essentially mistakes medium for content. The Weekly World News is no more journalism for being a newspaper than, say, Talking Points Memo is not journalism for being a blog. If you imagine video games as the vehicle for a narrative, the relevant comparison is no longer Michaelangelo -- it's genre fiction or comic books. I'm not entirely sure how Ebert feels about the idea of comic books as art, but it's clear from his citation of Cormac McCarthy that he does see some genre fiction as art.
Video games, like film, are a hybrid medium. But the nucleus of both is often the narrative. There is music in film, and the visual presentation matters, but I would find it as impossible to compare The 400 Blows to the Mona Lisa as I would trying to compare the performances of Alvin Ailey to the buildings of I.M. Pei. Different artistic mediums are difficult to compare to one another in any meaningful fashion. Video games, like comic books, will eventually have their Watchmen and Maus-level accomplishments. But if Ebert thinks they haven't, that is primarily the result of video games being a relatively new vehicle for telling a story -- video-game makers have only just really begun to tap the potential of video games as a narrative medium.
The early filmmakers, after all, aimed their cameras like they were taking photos, not like they were telling stories. Who could have imagined while watching the Lumiere brothers filming workers exiting a factory that we would someday have Avatar?
-- A. Serwer