Cast Away- Spoiler rant (mild)

SPOILER SPOILER SPOILER SPOILER!!

TURN BACK NOW!!
OK, here’s my beef, and I want opinions here. When I saw The Grinch, there was a preview for the movie Cast Away, which at first looked good. In it (it was a damned long preview) it shows Tom Hanks being RESCUED and the fact that his former fiancee has moved on with her life.

Does it not take away from the drama of the movie to know going into it that he comes out alive and OK? I decided right then and there not to see the movie. What’s the point? Why would they show such an important piece of the movie? Also, wasn’t there a Mel Gibson movie with a very similar plot?
This review site mentions it, too:
http://www.cnn.com/2000/SHOWBIZ/Movies/12/21/review.castaway/index.html

Any opinions on this?

Zette