It's not hard to replicate. My original post at the top explains it all in detail, and is echoed by everyone else here having this issue. In 10.6, using Spaces to move to/between any full screen VMware virtual environment causes the menubar and dock to show on top. According to Big_Banana, the developers are basically saying "Not our problem, upgrade your software" even though the System Requirements for Fusion 5 continue to state 10.6.7 or higher. Basically that says to me they still have an obligation to fix 10.6 bugs, regardless of whether Apple has stopped supporting the OS. If the developers aren't going to fix 10.6 bugs, especially one as annoying as this, then they need to adjust their System Requirements.
Off topic, I've also been waiting for VMWare to add in the option (when using 10.7 or 10.8) to choose between Snow Leopard style Full Screen and (Mountain) Lion style Full Screen. That issue is referenced here: http://communities.vmware.com/thread/340401?start=0&tstart=0 and has received strong support. Although completely unrelated to the bug described here on this thread, the lack of full screen options has been hounding me at work for over a year. Parallel's software offers the option to choose your type of full screen, which alone is enough to make me switch on the next upgrade cycle.