I love the update, though I’ve come across a pair of things worth mentioning, all on Window 7 64 bit.
The new windows in Cubase 8 don’t take into account the REAL border padding configured in the system. The default border padding is 4 but you can change it to any other value. Cubase 8 draws the borders always width a padding of 4, and this causes 2 problems: first, lack of coherency with the rest of the windows in the system, and second, if you have set the width to less than 4 (say for example zero, like me) you’ll see graphical glitches in the borders of the windows drawn in Cubase, and also the inability to drag upper border of the windows to change its size.
I still use white colour for the background of the editors and main window. Cubase 8 draws the items being dragged in a way that can’t be seen if the background colour is white, which is a real problem specially in the key editor. Also a selected automation points is really hard to see in the default bakground colour.