This is correct - the VIN tells all (well, in terms of MY spec anyway).
Sometimes the changes from MY to MY are more substantial or attractive than others. We missed out on the larger MFD on our Mk5 for example. This change came in with MY08 spec.
But it worked out for the better with the S3. After I had ordered the car I learnt there was going to be a spec change on the nav system, so I put back the build by 4 weeks to take advantage of the changes.