Fixed. Leadeboard is now divided into 2 categories. The Fallen, and the Unfallen. The Unfallen is not ranked by the length of the run, but it's just an ever-expanding list of the Unfallen heroes in order of appearance.
OH! Yea, to be categorized as an Unfallen, you have to survive at least 25 minutes and after that you can quit the game and it will be counted as being unkillable monster. Some anonymous took the first place on standard difficulty. Three more honorable mentions available (cadet, veteran and nightmare).