This is an issue for those who purchased a bulk volume license, they can add to that number of licenses by contacting MS and getting allocated additional licenses, even these fail the current and previous WGA validation as these numbers don't feature in the range of valid numbers they are checked against.
A friend who runs an IT business has a bulk volume license and his keys are legit, aren't doing the rounds so haven't been copied en masse, yet they still fail. He has written to MS complaining of this the second fiasco in less than a year. Having paid for the licenses he is pi**ed at continually having to get permission to use them. He wonders if it is worth the hassle, time and effort trying to resolve this with MS or crack the WGA.