Google is promising Gmail users whose accounts reset this weekend that they will have their lost data restored.
In an official blog post, Google claims the problem affected less than 0.02% of Gmail's user base, but it was a particularly nasty one as it affected more than one copy of the data.
Google's Ben Treynor explains how the company can restore the data: "To protect your information from these unusual bugs, we also back it up to tape. Since the tapes are offline, they’re protected from such software bugs. But restoring data from them also takes longer than transferring your requests to another data center, which is why it’s taken us hours to get the email back instead of milliseconds."
If you are one of the users affected by the bug, Google says your e-mail will probably be back "soon."