I don\'t think you want to make fall damage too \"earth-like\". People tend to fall down giant cliffs while trying to take pretty screenshots, and while some damage would tell the player not to do it again, killing them outright because they fell 5 metres would be annoying. If the player falls for a second (about 10 metres), they should die, anything under that the game should be fairly forgiving; just take a percentage of their health based on a percentage of a second it took to hit the bottom.
Obviously some areas would kill you right away (such as lava pits, bottomless pits, icy torrents, etc).