Interestingly, none of the spoilers I've read have said someone would be leaving the show, or even leaving permanently. I have the impression that someone is leaving NCIS, and will return next season. That was the ploy used in CSI: Miami last season when Calleigh literally put down her gun and left her ballistics lab. She never left the agency. If Bellisario is jerking us around, I think he's playing on out interpretation of the word "leave."

Didn't he say last year that someone wouldn't survive the finale? It was a much more specific warning, as I recall...