There are two new SDN tools in this release: Perfmon, and FlowLog Audit.
You'll see some tweaks to the visual styles: this leads to a more consistent experience with the Azure portal. There is also a new landing page in the add connection experience.
The effortless Azure Monitor onboarding experience has been expanded from a single server to include failover and HCI clusters.
For extension developers, the Active Directory search functionality that is available when adding connections is now available as a reusable control for anywhere you'd like to query AD in your tool.
Finally, WinRM over SSL (port 5986) is supported in this release.
Read the official announcement here: https://aka.ms/wac1908