MKS made one very good movie (The Sixth Sense), two decent movies (Unbreakable and Signs), and then he went crazy. Either that or he split with his writing partner on the first three, which I hazily remember reading somewhere.
His last three movies all have some potential and some salvagable material, but the endings are so utterly awful it all goes to waste. When I saw The Happening there were maybe twenty people in the theatre, and at least four of them made audible gestures of disgust at the ending.
The annoying thing is how flatly MKS keeps following the same formula that succeeded with The Sixth Sense.
1) Everything seems fairly normal on the surface, but we can tell there's something strange going on even though we don't understand why. Tension is created.
2) We gradually discover that some fearful supernatural/extra-terrestrial force is at work, accounting for our unease. The story becomes scary.
3) At the end we discover some shocking fact that completely changes our outlook on everything we've seen so far. This fact was never concealed, since evidence of it was right before our eyes in every earlier scene, but amazingly we still didn't see it coming. It also doesn't conflict with the resolution of the obvious plot.
It's a very effective recipe when it's done well. Unfortunately it hasn't been done well for three movies now, and when it's done poorly, it's a disaster. Parts 1 and 2 are still implemented with some skill, but part 3 is a catastrophy.
How about MKS directing some other kind of movie, eh? Get a new formula, at least. Stop trying to remake the same move over and over.