I'd suggest the reason the hood is discontinued is that the 800mm should take the same as the 400mm (I'm just assuming it fits), and they just haven't updated the 'accessory list' of the 800mm.
But then, they'll be a different colour (the new Big Whites come in the 'new white' colour same as the 70-300L and new TCs don't they?)
Maybe they just assume that everyone who buys an 800mm gets the hood included, takes good care of it, and never needs a replacement?
I'll definitely agree that it's not as 'due for replacement' as other lenses (like the list of 20-year-olds above). But with the 600mm + 1.4TC delivering almost as good IQ, there's not going to be many more sales of the 800mm (except for those who 'must' have 1600mm).
As for Point 2, i don't think that will stop them announcing anything. When they deliver is another thing, that won't stop them announcing tomorrow for delivery in 2015.