This one is cool. I've had it twice now, once last week and once this week.
You run setup and get an error before you even get to the dialog to select "Install" or "Create a Deployment".
"The system cannot open the device or file specified. C:\Users\(login name)\AppData\Local\Temp\_Axxxx.tmp\x86\en-us\Components\adr2013\SetupDesignReview2013.msi"
This happens because Trend Micro Anti-Virus is turned on and is protecting some files/folders. Disable it and run setup and you should be fine.
It could have to do with a particular version of the Anti virus, maybe updating it to the latest and greatest will resolve it, or maybe that's what broke it.