Well, most of the movies were already old when the park opened...Cagney, John Wayne, Oz, the musicals, Tarzan, Casablanca...
To be honest, that was what made me like MGM more as a movie-themed park, because it didn't go a untine route and just honor the big-budget teen-marketed "famous today, forgotten tomorrow" movies like many places might have. Thats why I like Universal, too, even though they and MGM are somethimes guilty of this. I'm not saying there's anything wrong with today's popular films, its just that I like the idea that there is a place like MGM that showcases these classics to the extent that they do.
Still, I am always ready for an update! Mabey this new script is just to hold our appetites 'till the much rumored re-doing of the attraction comes about.