Developers could refresh App Store's meta data for their apps at any time, but not anymore. According to 9to5Mac, which first spotted the change, Apple's iTunesConnect tool for developers used for editing metadata now requires that a new version of the app be submitted for review before its description, release notes and other metadata can be edited. Any changes made to an app's metadata won't go live on App Store until the new binary has been approved by Apple's editorial team.
UPDATE: Several developers we talked to have confirmed that this was indeed a glitch in the system, saying they're now able to update an app's description and other meta data without submitting a new binary for approval.