System Center Configuration Manager 2007 SP2 and System Center 2012 Configuration Manager SP1 now support Microsoft Application Virtualization (App-V) 4.6 SP3 Desktop Client and Application Virtualization Client for Remote Desktop Services. This client release enables support for Windows 8.1 and Windows Server 2012 R2.
No software updates are required.
As per Microsoft source: http://blogs.technet.com/b/configmgrteam/archive/2014/01/24/microsoft-appv-4.6-sp3-is-now-supported-on-system-center-config-mgr.aspx