Where have the 400's gone?
A few people are discussing the apparent demise of the lens. It's even claimed Canon stopped making them in 2004.
I know for a fact Canon Canada has run out of them as well as the 100-400. There is more coming they say. There has been an alarming number of backorders from Canada. The shortfalls could just be some new warehousing strategy Canon Canada is trying out, which by all accounts sucks.