I'll wait for 35L Mk II before I consider replacing my 35L, if ever.
HowEvar! The new Sigma 35mm f/1.4 DG HSM does look quite interesting..
You know, I just have this "thing" about 3rd party lenses. I know it's silly but I just can't get over it enough to buy one. But, on the other hand, I started shooting the EOS system ~15 years ago and I still use some of my original lenses no problem at all and they all still focus as quickly and as accurately as they did back then.
However, now that SIGMA has introduced a USB dock so that the user can upgrade firmware and adjust focus, I might be able to get over myself. Or if I shot APS-C, the Tokina 11-16/2.8 II would be pretty interesting. But I'm also pretty well set on lenses.
I don't see anyone who owns a 35L jumping ship to the new SIGMA but, seeing how they cost more or less the same, I would be curious to see the break down on SIGMA 35/1.4 vs. Canon 35/2 IS sales.
Is the 85L overrated? Well, it's a niche lens. It's probably the best 35mm portrait lens on the market. Nikon doesn't even have anything that's close. Now, is it worth the money? Not to me. I bought the 85/1.8. I didn't want something so unwieldy and heavy as the 85L and I wanted faster AF. And, if you stop down to f/2.8, the IQ is pretty darn close. In fact, other than purple fringing (but nothing that Lightroom can't fix), the 85/1.8 is pretty darn good even wide open. But nothing can match the bokeh and feel of the 85L wide open. If you shoot portraits, you'll want one.