Icons looks way better, but... sorry! :) I noticed that size M results in a much more rougher, jagged looking images still. Specifically I looked at the latest icons cicle, then new trash, and to make sure it wasn't just the new icons, I looked at random at another one, solid down triangle. They all exhibited the same behavior.
So there might be some rendering issues with 32x32 size. It is even noticeable in the designer, as you open the dialog to select an icon image and change the size there, you can see quality degradation in M, and also in XS, although once you select XS the actual image appears to look smooth.
Thumbs up for this update, great idea, I love it. Example images:
Sergei Khvatkov