Personally, I just don't understand why Canon would announce new cameras and lenses, then take months, or even years before they are on the market.
All it does it make Canon look foolish, or incapable to get a product to market.
All you do is stop sales of your current models, then piss off the people who want it now and even worse, give your competitors extra lead time to adjust their future models to better match or surpass what Canon is bringing out (eventually, if ever).
Wouldn't it be better if they only announced new product as it was about to be shipped?
You don't see many car companies announcing replacement models months in advance, nor any of the major electronics companies either.