I know, it sounds like the title of a movie- but it is not. The Ghent PDF Workgroup, who has developed many valuable specifications to make PDF delivery for print more predictable, announces the first Universal Proof of Preflight.

When implemented in a software solution, this best practice specification offers users the ability to review a PDF file’s preflight audit trail, including a digital signature, at any time during the design to print workflow.

This capability provides users the assurance that they can safely accept a PDF file with a Proof of Preflight. This process verifies which GWG preflight Specification was used to preflight the file and also the outcome of the preflight check.
SOURCE: QuickPrinting.com via Graphicstart.com

It will be interesting to see how this progresses as it sounds like a good idea.