Generally speaking... the concept tends to make me want to firebomb whatever studio is behind the damned thing. But, as with sequels, every great once in a while, they pull it off, so I'm not entirely against it. A couple have been mentioned here already: The Fly and The Thing, both of which revisited the basic material with considerable creativity and style.
I am, however, reminded of a story which Ellison has told on more than one occasion, of how a friend of his who was (if memory serves) one of the people responsible for development for one of the major studios told of a subordinate coming into her office terribly excited and just boiling over with this great idea he had, and how he just knew she'd love it, etc., etc., etc. So, unsuspecting of what was coming, she (who was by this time really getting pretty darned excited herself) asked "So what is it?"
Answer (completely straight, mind you): "Let's do The Wiz... white!"
And, after she managed to politely reassure this nit that she'd think about it, that it needed consideration, etc., until he was out of her office... she fell off her chair laughing, called Harlan still in stitches, and then they both fell apart. Until, of course, the fact that someone actually made such a suggestion in perfectly sober earnest, began to dawn with all its implications....
Things like this are why I've almost never attended a movie theater in the past 10 years.....