I take back my original observation. I had some issues to correct on how my guest and host were working. I access my host (Ubuntu Server) using VNC. From there I can either access one of my Windows guests directly from the VMPlayer console within the VNC view of my host or by using RDP direct to the Windows guest VM. My VNC server on the Ubuntu host was not configured correctly, and was giving me bad results.
After having fixed my VNC server configuration on my VMWare host, things are working very nicely. If I view a Windows guest from within the VNC view of my Ubuntu host (which is running in a 32-bit display mode), I do not see Aero effects. However, when I check the mode the display is running in, it definitely is running as a 32-bit true-color display.
When I RDP into a Win7 or Win Server 2008 guest, I get the Aero display. If I enable the Windows guest for access using VNC, I do not see the Aero interface, but the display is running in a 32-bit mode.
So it does appear that the "native" VMWare Player 5.0 video driver does not support Aero (in the device manager it shows up as the "VMWare SVGA 3D" device). Could be something to do with quality of the connection between the guest's virtual video device and the host's native video device. Or maybe they just disabled it due to too much overhead?
BTW, aero only shows up when using RDP if you RDP in from a Win7 machine. I do not see the Aero interface when I RDP into the same machine from a Win8 machine.