I, personally, have a familiar definition of "mass market film". I grew up in a small town with about nine total screens, usually one movie per screen and one screen per movie. Figure they turn over 4 screens per week for new releases. That's 208 movies per year. You'd need 3-4 more doublings to get it over 1000, so it's pretty clear that "hundreds" is the better order of magnitude.
I picked a year at random: 2008. The following movies were all released in 2008: The Dark Knight, Wall-E, Iron Man, Slumdog Millionaire, The Curious Case of Benjamin Button, In Bruges, Kung Fu Panda, Gran Torino, Indiana Jones and the Crystal Skull, and Quantum of Solace. Your average moviegoer will easily remember more than "one or two" of those (though not necessarily the same ones).
So the proportion goes from two in a thousand to maybe five in 250, or from 1 in 500 to 1 in 50.