According to the latest report, the Google Play Store’s new “Download Buddy” feature will roll out with version 33.5 of the app, according to the “what’s new in Google System Updates” page!
This feature was first spotted by @AssembleDebug two months back, and it basically lets you view the progress of apps you’re downloading while you’re browsing the Play Store. Here’s a video of it in action.
When it rolls out, there will be a “show download progress” toggle that controls this feature under the Play Store’s “Notification settings”. Its description reads: “Show a small indicator of download progress when using Google Play.”