Well, I've solved it.. not in the way that I wanted to though.
Bought Parallels 7, converted my Fedora 15 to a Parallels VM, then did a yum update to Fedora 16. Removed the vmware-tools and installed the parallels tools. Shared folders work again.
Not the ideal solution, but it works. So now I'm running both VMware and Parallels together (amazingly it works quite well). Most of my virtual machines are still VMware-based (I couldn't be bothered to convert them all), but this primary VM that absolutely had to have shared folders working is now running under Parallels. It's a shame, really, that VMware is lagging so much here.