Ok, let me quickly start with this.
I am an idiot.
I am not denying it, I am currently paying the price for a very stupid action; I have no illusions as to who is primarily to blame, its 100% on me ( well… and Microsoft ). Anyways….
Several months back I installed the Visual Studio 2011 developer preview, yeah not on a VM, but instead on my production machine(s). Yeah that was plural, my idiocy is compounded. Of course I know I shouldn’t have installed it in production, but simply put, its new and shiny! Besides, they actually say it will install and work side by side with Visual Studio 2010, so I listened to them!
Then, as is the way of things, I started running out of space on that hard drive partition and since I wasn’t really using it I went ahead and uninstalled Visual Studio 2011. So, Microsoft says it will *install* side by side with VS 2010, which is true… it just won’t uninstall!
After uninstalling the 2011 preview, I opened up a C++ tutorial project I am finishing off and:
C:ProjectsGameFromScratchGFSCPPPang9Pang.vcxproj : error : MSBuild does not contain a value for the "VCTargetsPath" property.
Ahhh crap.
My Express install is also broken. Joy. 
I think this can be fixed, apparently VCTargetsPath is a registry key setting, but once these kinds of things start cropping up, I get paranoid about my build environment. Long story short, it looks like a re-install is in my future, and that sucks.
But yeah, I know I am the one to blame.
Anyways, time for the TL;DR section.
If you installed the VS 2011 preview on a production machine, DO NOT REMOVE THEM!
And shame on you, you should know better than to install pre-beta software on a production machine! 
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