An AIIM study into the usage of PDF in organizations has found that 90% of organizations are already using PDF to store and archive their documents, as reported by GCN.
The introduction of PDF/A (a subset of the PDF spec, designed for long term document archiving – http://en.wikipedia.org/wiki/PDF/A) would be one of the main contributors to this.
Nitro PDF Professional 6.0 will include the ability to create PDF files that conform to the PDF/A-1b spec.