some thoughts: - i have cron jobs that run roll-up reports on a scheduled basis on GAE. they select all rows, bucket them, and store the data in an easy to query table. this should be replaced by the recently released Map-Reduce API for app engine. - i am beginning to experiment with Google Cloud Sql for storing stats data. this will allow my admins to run arbitrary stats reports at the expense of data duplication. cloud SQL itself is in (private?) beta still and pricing has not been announced.
cfh
