1. [mass noun] the expression or application of human creative skill and imagination, typically in a visual form such as painting or sculpture, producing works to be appreciated primarily for their beauty or emotional power:
In the first definition of the word video games easily can be classified as art. Many "artists" do work together to create video games, and the best of which are appreciated for their beauty and emotional power. I know many people may say a video game has never made them cry (I would be one of them) but I bet many games have evoked feelings of fear, excitement, or any overall care for the main protagonist and outcome of the story in almost any gamer. It is a medium that gets its message across beyond using language, and for that it fits the most basic definition of art.
The debate should not be whether video games are art or not, it should be how can we progress this art form to be more accepted in society. There was a time when rock and roll would never have been considered art, and now the Beatles are hailed as the brilliant artists that changed music forever. Cartoons would have been seen as simple children's entertainment, but now I dare you to find someone who does not consider Walt Disney an artist. Video games will have its time in the main stream spotlight as a serious medium one day, we just have to hold it up to that light.