VMware released vSphere 6.5 Patch 02 at December 19, 2017.
It seems the Patch 02 is limited to enhancements on vSAN only. Adaptive Resynchronization is an interesting new feature.
John Nicolson has a blogpost with details.
Taken from the VMware KB article
Adaptive Resync adjusts the bandwidth share allocated to Resync I/O to minimize impact to client I/O. With this feature, Resync speed will adaptively adjust during off peak and high peak I/O cycles. During off-peak cycles Resync will speed up and during high peak cycles Resync will slow down. This ensures Resync continue to make progress while minimizing impact to the client I/O.
Enhanced support experience powered by vSAN Support Insight
Enhanced support experience powered by vSAN analytics is available to vSAN customers who enroll in the CEIP (Customer Experience Improvement Program). VMware Support can inspect individual customer environments, understand configuration, runtime status, performance and more in close to real-time based on rich dashboard and analytics engineered for VMware Support.
Multipath support for SAS systems
vSAN now enables multiple redundant paths from server to storage with no setup required, when used with a supported multipath driver. An example of such a system is HPE Synergy.