Supermarket 2.8.3 was released this week. This was primarily a security release to resolve CVE-2016-6316.
For more details about the changes in this and other releases, see the Supermarket changelog.
Also, this release marks the transition of Supermarket to an Automate Workflow pipeline. Releases following 2.8.3 will very likely not have contiguous, sequential PATCH numbers, but will follow BUILD versioning as described in the Chef Release Process. We’re still working out what the changelog will look like in this new process, but at a minimum builds that have been promoted to releases will have their tags promoted to release records on the Supermarket GitHub repo. The release records will have an annotation collecting changelog-style entries for all the changes since the previous release.