Love my 100-400, would appreciate better IS, full sealing, and optical improvements. If it's as sharp as the 70-300L, awesome. Hope they keep push-pull, but could learn to live with rotating extension.
Expensive, yes it will be. But probably worth it.
100-400 F4 without 1.4 extender, Would be a good alternative to the 200-400 maybe half the cost?
Ha ha ha. 100-400mm f/4 means the same front element size as the 200/2, 400/4, 200-400/4, etc. Would be a $7K lens easy. Get off this, folks, it'll be f/5.6 at the long end, and likely close to $3K at that.
Yes, I'm with neuro on this.....
I have used Canon's existing 100-400mm L, and it can be a great lens. The newer 70-300mm L is definitely a design & size I prefer (and it's IQ is consistently better). Personally I prefer rotating ring zoom rather than push-pull, but I could get used to push-pull too.
I really love my Canon 70-300mm L on my 7D. And I'm sure that a new (improved) 100-400mm L with a 7DmkII would be a welcome 'tele kit' for many. However the new / rumoured 100-400mm couldn't be a constant f/4 without being huge, expensive, etc... and I expect - Canon have the 200-400mm f/4 1.4x as a separate target lens.
Looking forward to this CR2 becoming a CR3... especially to see what the 7DmkII will bring! (Improved IS and if possible better AF, within still 'non-pro budget' for the 100-400mm will see some good sales, I expect).