I miss the track details bar at the top of the current selection of music. I always found it very helpful. Right now if I open up a smart playlist I have no idea how many tracks are being returned.
I personally don't need the length and total size but it would be nice if the bottom bar, where it shows the total size of your selection, would display the number of tracks currently in view.
We will see how we can improve this.
For some of the views today, the actual items (tracks/albums/artists) are shown into the upper right/lower bottom.
This can most likely be improved and made more consequent.
More accurate displaying (not selected tracks yet) are implemented in: