It would seem that ATSB are posting out hard copies of this report to (at least) Chipmunk owners - mine arrived in the mail yesterday.
Given that everyone seems always ready to bag ATSB, I think it's impressive thinking to ensure that this report receives the widespread attention that it surely deserves.
The attached "The Chipmunk Spin - The Facts" article (from Aviation Safety Digest No.22) is also included, unlike what was on the ATSB website this time it's large enough to be easily read. It should be required reading for all Chipmunk pilots or those intending to fly one. To his credit, Roundsounds ensures his students read this.
Lastly, on another thread Sheppey posted this:
aircraft owners should be particularly interested because of the need to always ensure aircraft flight manual documentation is valid and up to date.
Perhaps missing the point here, the major significance is that at least two instructors (and they were from a school that had another Chipmunk "on strength") weren't teaching (or perhaps didn't even know) the correct technique for Chipmunk spin recovery.