A question which comes to my mind is - what will happen to the 14mm f/2.8L II lens if a 14-24 f/2.8 L is released by Canon? I guess the prime will be pretty much dead unless at 14mm, the zoom is NG.
I've tried out two copies of the existing 16-35 and didn't see substantial improvements over my 17-40 (which I sold). While I'd love to get a 16-35 III or a 14-24 Canon doesn't seem to be in a mood to release either of these lenses, I'll be buying the TS-E 17 next month.
1DX, 5D3, 600D, RX100
16-35L, 24-70L II, 70-200L II, 100-400L II, 50L, 85L II, 135L, 17TSE, 24TSE, 40, 100 macro, 18-55 II, 55-250 II, 1.4x III, 2x III, 600RT x 4
When it comes to gear, it is better to vote with your wallet. Bitching on online forums like a lunatic doesn't get you anywhere!