Do you care about IQ?
70-200 II is not able to replace 85/135/200Ls in many situations...
IQ? The 70-200 II is equal to or better than most of the primes in it's focal range in terms of IQ - basically, the differences are so minor as to be marginal in rigorous testing (charts/Imatest) and practically irrelevant in real-world shots. The reason for the fast primes used to be IQ, shallower DoF, more light, and smaller/lighter (for a single lens, not the set). At this point, for all practical purposes, it's down to shallower DoF, more light (debatable with a newer FF body and the excellent high-ISO performance) and smaller/lighter.
Which is exactly my reasons for getting primes in the first place, but now I see the 24-70 and the 70-200 mk2's and to ME the incredible AF-speed of the zooms along with equal or better IQ, I'm getting rid of some primes. I'm keeping the 35 and 50 as the shallow dof favorites and getting the 24-70 instead of my 24 f1.4.
As always the 85 L is incredible! but what good does that do when the AF just can't cope with tiny rapid movements or my kids walking across the floor, to get sharp images I need to get more dof, stop it down to 2,8 helps, why not then use a 70-200 instead.
The only reason for fast primes for me now is shallow dof. I get MUCH better indoor images at iso 400 and flash to the roof than with 1,4 and iso 6400....