In the above, the icon images themselves are the same size in pixels. However, the horizontal spacing of the buttons is about 25% bigger in the WIP (for no real reason I can see).
Also the text font on the buttons with text has changed quite noticeably, it’s about 25% higher and 35% wider than in V8.
Lastly, the icons are still somewhat blurrier than in V8. Below at 400% in PS: