AdWordsAdvisor - 12:14 am on Oct 28, 2010 (gmt 0)
Hello again - back with a quick update from a Product Manager colleague who reports:
I can confirm that this issue did not impact serving (i.e., the system has been correctly computing auction-time Quality Score this entire time for ranking and pricing purposes).
This issue was limited to the reporting of Quality Score, and the fix should be live for all within the next 24 hours. For those keywords with a status of Low search volume, the fix should be live within the next few days.
Thank you all for your patience as we resolve this.
To which I would add my own 'Thank you' for your quite notable patience and calmness in this thread!