Noticed that with the new version also Google Music was unavailable for me, and yet it is there with the old version.
I think the leak version might only be suitable for certain devices ?
Altho you probably already got an answer, I saw that the new Play Store was incomplete for consumers outside the US.
I installed and love the new layout, but it mostly has to do w/ the white color scheme. It gives it a more updated/modern look. My gripe w/ the Play Store has always been that it looked... cartoony? Given the black + every other color, color scheme.
One thing tho, icons getting reduced in size will likely be an unwanted change. For example the update button is probably less than half the previous size.