I put in a call/ticket to the Consumer Security Support Center - 866-727-2338 and reported the issue as it is also affecting Microsoft Security Essentials, but I doubt that will do much good. The tech I spoke to wanted me to do a system restore (TYPICAL!), and her manager was "on break".

I'm not sure where the front door is to report an issue such as this.

There is also https://support.microsoft.com/oas/default.aspx?&gprid=14910&&st=1&wfxredirect=1&sd=gn, but you've got to pay to submit the false positive (under Malware Detection). However, I can't seem to use a software assurance ID to report the issue - I get an error page - maybe somebody else will have better luck?