I think it's always going to be 'horses for courses' as they say.
Shooting sports and nature, the 1D4 was the natural choice. I want an AF system that works fast. Check. I want fast fps, Check. I want to not worry about getting clobbered by a player, mud, footballs or rain. Check check check.
I looked long and hard at the 7D and was very close, it's a fine camera.
5D2 not in the running. As you said Mike, it's a fine wedding camera and would be first in my bag for that.
Resale value? Didn't really think about it like that. As and when it goes and something new comes along, it'll be worth what people will pay. But methinks it might be a while yet (and the bank balance will have the final say, as ever lol).
It is a lot of money, but it is a lot of camera. And as someone said, if its sport/nature/journo work then join the queue, you won't regret it.
I love mine, can you tell? lmao.
Best of luck with your choice OP.