There are many VMware and Citrix customers happily running Citrix XenApp and XenDesktop on VMware vSphere clusters with Virtual SAN enabled.
Citrix XenApp is fully supported on VSAN.
Citrix XenDesktop PVS is fully supported on VSAN.
Citrix XenDesktop MCS is still not supported on VSAN by Citrix at the time of this writing on October 7, 2016. Citrix has a fix that is in 7.8 and 7.9 already and customers have reported that the fix works, however Citrix claims the fix has not been qualified by them and thus is not supported. ETA for their official support is unclear at this point but is the responsibility of Citrix. If you are needing this feature, please reach out to Citrix to let them know.
Our friends at Dell Technologies (EMC/VCE) have tested XenApp, XenDesktop PVS and MCS on VxRail and have produced a report here:
Citrix XenDesktop 7.9 and VMware vSphere 6.0 with VCE VxRail Appliance
In it they state “Citrix official support of MCS on VMware Virtual SAN is expected in a future release of XenDesktop. EMC tested this configuration and found no observable issues.”
For the record, I’ve been a fan of Citrix since I first deployed Citrix WinView in my data center and remote sites back in 1994. Yes, I’m that old. I’m sure this will all get worked out.