Art is passion made life.
The difference between a picture and art is a passion for one's creation. A four-year-old can create a work of art where a professional artists couldn't simply because a four-year-old's scribblings often speak openly from the heart and interests of the child whereas the artist may just be looking to get paid. I think society has a bit of a confusion between pretty and beautiful. Pretty is pleasing to look upon, beautiful is a piece of the soul. Limbo is considered an "artsy" game because it is most certainly pretty. It may not be good-looking, but its art direction combined with movement and music make it provocative, compelling and fraught with dark undercurrents. It is most certainly thought-provoking, but is it truly art? Is it a truly beautiful game? That question can only be answered by the discovery of the intent of its creators.
Not to say that pretty things are bad, in fact, they're certainly much more fulfilling to experience, but beautiful things are much more fulfilling to create. I find fulfillment at its absolute peak to experience art with a balance, something that is both pretty and shows just a bit of emotional attachment, the stronger it is, the more detectable it is. The more detectable it is, the better.