Currently on Giant Bomb, once you have a list that gets above 600 items or so, you can't actually edit it anymore. When you try to save the list, it just loads forever. I guess lists weren't originally meant to be that big. The only option you have at that point is to add things to the list by clicking the "Add to List" button on that item's page. But, then you're not able to organize the list.
So, anything added to this list after February 7, 2012 will be found at the very end of the list and not alphabetized into the rest of the games. Hopefully this will get fixed someday.