I don't get the hype about this lens.
Wow, that's a lot of misconception there, to be charitable...or trolling, to be uncharitable.
There is already a 70-300L out, which does have 100mm less, but you can get that with a 1.4x TC for cheaper than this 100-400 is supposed to be.
Do the Canon TC's work with the 70-300L? In case you didn't know, they don't. 3rd party TCs do, but the newer ones will not AF, and regardless, that option is pretty inferior, optically.
Or maybe you're suggesting no one needs that extra 100mm? If you
don't fine - say so. Personally, I do...
For every f/2.8 70-200 II owner, this 100-400 lens is just pretty useless.
Ok, I own both, and a 2x TC. Does that make me an idiot? Do you own both? If so, maybe that makes you an idiot. If not, then how do you know the 100-400mm is useless? Maybe having both would give you the opportunity to test the 70-200mm + 2x against the 100-400mm, in which case you'd find out that the 100-400mm @ 400mm f/5.6 is optically better...
First, you're blowing away 100mm worth of f/2.8 super high IQ goodness
Then, if you need the reach, just add a TC and you got it with probably similar IQ.
This makes no sense at all. They are different lenses, and no, adding a TC doesn not give simliar IQ. Decent IQ, yes. IQ that will do if you don't have the 100-400mm with you, or if you're shooting in the rain and need a weather sealed combo. But not similar.
What any 70-200 II owner needs is a 200-400 f/4 and not this rubbish.
So...you're going to give everyone the $8,000 (estimated) to make up the difference in cost? Apparently, you're very generous, and you're independently wealthy, or being a doc in the former Soviet union pays a lot more than I've been led to believe.
If you dont have a tele lens at all, 100-400mm gets you covered nicely in once package, but if you have a 70-200, it's kinda useless.
I think you said that, already. A 200mm lens is no different than a 400mm lens? Or a TC is a magic tube that doesn't degrade the optics at all? Consider...if the current 100-400mm beats the 70-200 II + 2x TC at the long ends, how would a 100-400mm designed to the current Canon trend (24-70 II, 70-200 II), with the newest coatings, etc., compare? Answer: it would blow the 70-200 II + 2x out of the water.
But you must be right. A new 100-400mm lens is useless. Canon is stupid for spending R&D funds on one, and they'll never bring one to market because no one will ever buy one.