I felt the buildup to the ending didn't suit the ending. The twist at the end of the movie is similar to the ones in Shyamalan's previous movies, but this twist is nowhere as significant. I guess the ending left me a little empty.

The acting is stellar. Mel Gibson plays a priest who's lost his faith in the face of tragedy with great accuracy. The rest of the cast is also strong. It is apparent the director wanted to show how the issues within the household took over other problems. But it is still hard to believe that a family would still be trying to sort things out when chased by an alien and stuck in a basement with no escape.

This movie is bound to spark other UFO movies, but none will match this one. This is because most other (all other) UFO movies are approached as Sci-fi's, whereas Signs is really a drama where aliens are just another obstacle in a story coming from a totally unrelated matter.

In short:
Comedy: Some quirky comments, especially the kids
Violence: A few chases, but this one is mostly suspense only
Nudity: None
High Points: Directing, lots of suspense, good acting
Low Points: Ending anti-climatic, a few weak points in plot