After the first reports of mass email deletions on some Gmail accounts, Google responded. They basically said two things:

1. It’s a small and isolated incident, only about 60 accounts had their emails deleted - which is good news.

2. There is no backup.  OK, this is scary. No backup? Or did the backup also got deleted? One way or another, I hope Google learns a lesson from this relatively small incident and add some additional backups and safeguards for their services, because if this happens again, users will be very angry.