Canon 16-35 f/4 L IS

I’ve been using the Canon 17-40 f/4 L for 10 years.  It was actually the first lens that I bought with my first DSLR, a Canon 10D.  That thing has been a workhorse for me, but there’s room for improvement in the corner image quality so I’m hoping that’s what we’ll see from this new lens just announced by Canon. I’d guess that this is a replacement to the old 17-40, though it’s not mentioned as such directly.  Of course, there is also the 16-35 f2.8 L II, but the addition of a 4-stop image stabilizer to this new lens