Google's Play Store has changed much over the years, transitioning from the antiquated Android Market into what it is today. The many changes also included a few shifts in the visual design, the most recent of which Google gave users a taste of yesterday with a teaser image of what the new UI will look like for the Play Store soon. That UI refresh also started to roll out to some users as of earlier today, but there's more to be expected besides some tweaks to the interface. like updated support for books to be listed off and categorized by series which should make it easier for users to find the books they may be looking for.
The first thing of note users will likely see in the upcoming Play Store update besides the new UI is a more recognizable detailing of how big specific applications are. One of the biggest issues for some people with their smartphones is storage. Apps and games these days are getting bigger and bigger apk's albeit not all of them, and Google wants to make it simpler for users to be "in the know" about this kind of information so they may be aware of whether or not they have enough space on hand inside of their device storage to accommodate an app or game. With the new update, it looks like Google will be listing app and game apk sizes next to or within the vicinity of the buy and install buttons.
There will also be some changes coming to the books section of the Play Store as it appears Google will be making it so that users can categorize books by series when they're looking for something new to read. This should make it much easier for users to find subsequent titles to a particular book they may have enjoyed. For example, if you aren't familiar with George R.R. Martin's A Song of Ice and Fire series, these new organizational listings would make it simple to find every book in the series with little effort. In addition to these changes, it also appears Google is adding in surveys for when users opt to refund an install purchase so they can get a basis of the reasons for the refund. While the update to the Play Store will start to hit users soon, you can download the apk now if you don't want to wait.