VMware has just published a KB article (KB 2086946) [Temporally down] on using Microsoft failover clustering services to support high availability of vCenter 5.5 U2. My assumption for this support is the demise of the vCenter Heartbeat product. I appreciate VMware giving customers a new choice for vCenter high availability.
Slightly buried in this gem of a KB article, in the original version, was the new support for using SQL 2012 Always-On Availability Groups for the vCenter database! However, the KB was since pulled and I’m told by VMware it was published in error. In fact, AAGs have not been qualified and are not supported for the vCenter database. If you are a customer that wants vCenter DB SQL AAG support, then escalate to your TAM and make your opinion heard. In case you missed it, vCenter 5.5 does support the ‘traditional’ shared storage SQL cluster configuration for vCenter.
SQL AAGs are still supported on vSphere in the general sense. This new KB article was for the specific instance of the vCenter database. If you want to see the full support matrix for Microsoft high availability solutions, check out this article.
Prior to the KB being pulled it stated this: