Game theory tricks your mind - monty hall problem

I like these game theory stuff. Here's one dilemma and it's solution.

You are in game show.
1. Host gives you to choose from three doors, which one of those contain main prize, other two something minor.
2. When you have chosen the door, you can't open it yet, but host opens one of two remaining doors to show that main prize isn't there.
3. Then he gives you option to swap. Should you?

Check the dilemma and well explained answer:


I might be bit strange, but I just love these mind tricking dilemmas.  

Written by +Henri Hämäläinen