Via a Perl Script, a very helpful post can be found here:
http://www.linuxdynasty.org/how-to-check-the-status-of-vmware-tools-per-virtual-machine-the-easy-way.html

If you’d rather use PowerShell, check out this helpful blog post which also references a follow-up VMware community post:
http://philthevirtualizer.com/2010/06/22/powercli-get-vmware-tools-versions/
http://communities.vmware.com/message/1722648