VMware publishes two independent, but equality important compatibility lists: the Hardware Compatibility Guide and the Product Interoperability Matrixes.
VMware’s Product Interoperability Matrixes is definitely the lesser-acknowledged sibling of VMware’s compatibility lists. Often overlooked after the hardware is supported, the Product Interoperability Matrixes help navigate the increasingly complex web of intertwined VMware products. After you progress beyond basic server consolidation and improved disaster recoverability with Site Recover Manager, you need to take into consideration which versions of Site Recovery Manager are supported with new versions of ESXi and vCenter. Moreover, what about virtualizing the network with NSX? You most definitely should verify support before upgrading ESXi and vCenter following a new release. What happens if the newest version of ESXi does not yet support the older version of NSX that you have not gotten around to upgrading? This could lead to large, unplanned downtime that may not be possible to test in a lab environment without spare time and evaluation licenses.
As much as dotting each I and crossing each T can be a pain and seem unnecessary, especially after things have been stable for so long, I must urge everyone to verify not just hardware support, but also support with intertwined products before jumping to the latest, greatest new version with the sparkling bells and shiny whistles. VMware has released two fantastic resources with the Hardware Compatibility Guide and the Product Interoperability Matrixes, but do not forget to consult your other intertwined products (e.g. backup solution, replication appliance, etc.).