http://www.wga.org/subpage_newsevents.aspx?id=1807
A friend sent this list from the Writer's Guild of the 101 Greatest Screenplays and it's an odd statement. The overall impression isn't that screenplays were judged but that the voting members simply chose the greatest films where the screenplay was clearly the foundation. How else would you account for Citizen Kane when it's obvious that the same script filmed by anybody else but Welles wouldn't have resulted in anything remotely like what we have. Or The Wizard of Oz which owes less to the screenwriters than to the songwriters, actors, set designers and Baum. The number one choice was Casablanca, a routine 40s Warner melodrama that's inexplicably come to be considered A Great Film but which again owes whatever strengths it has to something other than the script. (It probably helps that respected nitwit Robert McKee has praised this particular script, or again the resulting film since it's not clear that he or any of the voters actually read the script.) Being the result of industry voting, the list really just shows writers patting each other on the back. That's why there are no silent films and almost nothing from outside Hollywood.