The rule of thumb is all large electronics need to be able to seen. Like, if an xbox was to come through with lots of wires around it, it would be hard to determine if there are dangerous items around it. It's soo much easier to see electronics if their aren't lots of clutter around it. We say laptops b/c they are the most common large electronics carried around by passengers. I think people would look at me crazy if I started asking everyone to take out their PS3's out of their bags lol.