Starting today, owners of devices with Lollipop will begin to notice some changes in the Play Store. The latest version, 5.4, introduces immersive hero images throughout the application. Coloring, sizing, and placement have all been altered in certain areas, too. The changes are not considered part of an overhaul, but something like the transparent status bar is noticeable.
The evolution of the details page can be seen here:
Source: Kirill Grouchnikov (Google+)