Some know issues are :
ePolicy Orchestrator 4.6.4 is currently Released to World. This means that the product is available to all customers via the McAfee downloads site or McAfee ServicePortal.
CRITICAL: No issues at this time
RSD automatic responses break on upgrade from 4.6.3 to 4.6.4.
Following the old KB73602 fixes it (thank god I kept a printout), but it would be nice if McAfee properly tested things and fixed the underlying issue.