Yea, but there is this comment, from Intel.
Hopefully we shall see an official statement, from the MB manufacturers. They were supposed to make non Z overclocking, but they did it anyway.
Addition 10/21: The quote direct from Intel is that 'we do not validate or support Xeon E3 SKUs with client chipsets'. This has always been the case in the past so nothing on the official line has changed, and at this time Intel is not making any additional comment to the adjustment in compatibility.
Hopefully we shall see an official statement, from the MB manufacturers. They were supposed to make non Z overclocking, but they did it anyway.