benji, that quote by lewis is quite literally so famous people truncate it down to "When I became a man I put away childish things" and the people they talk to understand the point being made. In popular culture it has supplanted the bible quote it riffs on. Have you really not heard it before?
edit: also, reddit trashes gaf in terms of popularity. Both as a video game message board (4million on reddit's primary gaming sub alone, nevermind the game/community specific ones) and as an pr/community interaction platform for game developers.