Here is the letter in full, courtesy of TechCrunch:
Google wants to expend and to practically own the Internet but they neglect their current services. This comes after two weeks ago, Gmail was down for about 3 hours, so the trust in their services is going downward.Dear Google Docs user,
We wanted to let you know about a recent issue with your Google Docs account. We’ve identified and fixed a bug which may have caused you to share some of your documents without your knowledge. This inadvertent sharing was limited to people with whom you, or a collaborator with sharing rights, had previously shared a document. The issue only occurred if you, or a collaborator with sharing rights, selected multiple documents and presentations from the documents list and changed the sharing permissions. This issue affected documents and presentations, but not spreadsheets.
To help remedy this issue, we have used an automated process to remove collaborators and viewers from the documents that we identified as being affected. Since the impacted documents are now accessible only to you, you will need to re-share the documents manually. For your reference, we’ve listed below the documents identified as being affected.
We apologize for the inconvenience that this issue may have caused. We want to assure you that we are treating this issue with the highest priority.
The Google Docs Team