Saw the episode. Although I heard the actor was leaving the show, I never thought they would actually kill the character off. I thought it would be that they either left the expedtion, or was "lost" on a mission. The writers actually suggested a while back, that the character would remain alive, so that was sort of a shock seeing him/her get killed off like that. Although he/she did get a fitting ending, I grant you that. Fits well with the character.
edited to hide gender of character so as not to give it away. Pegasus
Edited again cos you missed a bit. El