It's interesting that you don't seem to be addressing the defense of gaming as art. You've got your work cut out for you because you would have to argue what exactly art is (or is considered to be), why games could be considered art, and then further expand on a point for your thesis.
Interestingly enough, the internet hellstorm that kicked up because of Roger Ebert's statement about games not being art didn't address the core similarities between movies and games. Both are entertainment mediums that tend to be: 1) assembled by hundreds if not thousands of individuals, 2) for the most part motivated by profit, 3) created with the sole intent of distribution and mass consumption, and 4) for the most part controlled by a single director (see the documentary Tales from the Script). The third point about mass consumption stands out to me as a basic, core principal of what exactly art is.
Ignore the fact that I don't have an art history degree and imagine the first cave paintings ever made (in France I believe). Somebody probably intended to simply illustrate a story or perhaps create a rudimentary guide. Those paintings consisted of representations of early humans and the various animals they hunted. Ultimately, I think what validates the importance of those cave paintings is they were recordings of a genuine human experience, if not THE genuine human experience of the time. But the mere act of painting, recording those thoughts, says something about the basic intent behind "art". Art isn't something that can exist only in the mind. The mere act of creation goes with the understanding that what you're making is meant to be seen, experienced, and ultimately judged by others.
So if you compare the oldest cave paintings ever recorded against a game like Space Invaders then the game certainly doesn't seem like art, but it DOES represent the human experience. How so? Well, Space Invaders was one of the first arcade games ever made, later making its way onto the earliest gaming consoles. It's representative of mankind's silicon age, or the age of information. Space Invaders was part of humanity's initial shift into another modern era. There aren't many examples of entertainment that are as important. And let's not forget that entertainment or the pursuit thereof is considered to be one of the core requirements in the definition of intelligence. Technically, it's the capacity for play, but I think it still applies.
Mass production also doesn't stand as an argument against games as art. Consider the fact that old appliances are thought of as beautiful. Companies like KitchenAid, Apple, and Braun are considered to be makers of beautiful, manufactured products (see also the excellent industrial design documentary Objectified). Mass produced posters from the Art Deco era (and even cars and appliances of the time) are considered art as well. Art Deco architecture, fashion--they represent a specific, historical era and are cherished as only art can be. And let's not forget the fact that the Smithsonian had their very own video games exhibit.
http://americanart.si.edu/exhibitions/archive/2012/games/
I personally don't think it's a good idea to consider certain gaming titles as being art just because of their visuals. I think your typical, trite examples of 'games as art' would be titles like Okami or Windosill. Yes, they make great screenshots but I think it's a fallacy to think that just because something is pretty that it's a good example of art. I would consider titles that had a more emotional or visceral impact like Slenderman or Prince of Persia: The Sands of Time. Anyway, sorry for the long post, and good luck.
