This was a topic previously discussed by a few members in the off-topic thread, and although we wrapped things up nicely, I thought it would be a good idea to revive it and give us something to talk about. Do you believe some games are art? Are all games art? If not, can they be art? These are three questions often tossed around internet forums, so it's only appropriate we have a larger discussion here.
I personally believe all games are visually art, but something I dub as mental art, in which something touches you mentally, has only been achieved by a few games. What I see as true art is the MGS series, Shadow of the Colossus, Ico and Okami.