Two days ago we reported that on Google AdSense Reporting Discrepancies, which actually started sometime on Monday.
In short, the channel reports were not matching up with the aggregated reports. So any reconciliation between the two reports did not add up.
This has finally been fixed.
Last night at about 6pm (EST), the first reports started coming in that the channel data has been updated.
As of the 3PM Pacific hour I'm starting to see increased channel impressions. Not sure yet if it's back to normal as the channel data historically had a 30 minute (or so lag) for me. Either there may be headway on the issue or my SERPS have undergone a major change.
Forum discussion at WebmasterWorld & Google Groups.