Thanks Michael for running that time comparison! A lot of folks had that exact question in their minds for a couple of months now!
I imagine 70 seconds would seem like an hour if you were shooting a wedding with everyone staring at you as the seconds tick by, and you start to sweat.
5d3 owner here, has used it on multiple weddings. I don't find the lag time to be too much of an issue because the AF lag only happens in extremely dark situations -- like when your going with no flash ISO 6400-12,800, f2.8 or lower, 1/50th SS ---- in the kind of situations you probably would get a shot at all with a 5d2 or 7d. For a while i was running with the 7d 5d3 combo and found that yes, the 7d would achieve focus quicker, but the shot was totally unusable...
shot posted from a reception, ISO 6400, f2.8, 1/100th, 140mm
Also, i have found the focus speed to vary depending on lens used, and aperture used, and which AF mode I'm in. Using either of my primes wide open, with single point AF the lag is much more noticable. But, at f2.8-4 losck is achieved much quicker. And if I used expanded AF points focus is also quicker (less precise though). I see it as a trade off, if I am shooting wide open on prime lenses, I'll accept the lag time in order to get a precise shot! So for me, while it would be nice if it locked quicker, I'll take the trade off!