I can confirm that this is happening currently on Windows 7 and 8 boxes but only if we use OpenDNS. Google DNS works.
This first happened on 7-27-14 but only Win7 boxes that had Windows Update Agent 7.6.7600.320 installed. If system restore was run prior to that Agent update all was good, until that update went back in.
On the 28th, at least on OpenDNS, the problem disappeared, only to reappear today on both Win 7 and (some) Win 8 boxes. I have not had enough troubleshooting time on Win8 boxes to test further.