[DaveWalk]

As a scientist, two things come to mind:

1) Tenure is a different beast at some medical institutions where your funding comes almost entirely from your own grant support. There are tenured professors and it's fair to argue that tenure is important as a promotion, but if a tenured professors loses his/her grant funding, they can lose their office just like their un-tenured associates (I've heard of it but have not seen it personally).

2) The bigger problem is that tenured professors leave and head for prestigious jobs in the private industry. I always wondered why this was the case; I was enlightened talking to a spouse of a prestigious professor who said that in general the academic system treats even the tenured professor terribly. The big, big opportunities (and accompanying explosion in salary) are only in the private sector.