According to a count of those listed in IMDB, that makes at least 23 in 100 years of movie making or a new one every 4.3 years. And tat does not include all the derivative cartoons, music videos, sitcom adaptations, radio plays, audiobooks and PBS style reviews.

I can certainly leave the newest WH unwatched. From now on the only Heathcliff I'll be viewing is a cat in the funny papers.