I checked this out and here is a quote from the Save Enterprise WEB site: .
The site (which is hardly friendly to Nielsen) claims to have taken this from Media Daily News, but when I checked, I could not access that far back (early Feb).
There are the quotes about impacting 'strategic planning', but if the information from Media Daily News is accurate, I can't imagine that any company is basing their decisions on three months of the most recent data--most especially if the data were not consistent with the prior months results.
There are some other sites that duplicate this same information from MediaPost. Basically it does not look particualy serious and it appears as though the bad data was corrected quickly (the Media report is dated Feb. 14).