Why did you call Pioneer to complain about something that Apple did?
When it comes to firmware updates, there are certain aspects that are not changed. This is so a company such as apple can update a product and ensure it is still compatible with other items: Adapters, plug-n-play stereos, yada yada yada. Most companies base their connectivity between their product and the ipod on this information and therefore usually have no problems when a new firmware is released. This is why when I plugged my iPod into my friends 7150, it still worked. Same goes with my coworkers alpine, as well as various docking stations I have tried since it started to fail.
It is entirely possible that whatever pioneer had their unit coded to read, was not based on this standard for ipod connectivity. If this is the case, pioneer is in the wrong and would have to issue an update. You cannot blame apple for a failure if pioneer went about it in the wrong kind of way.
Now, this may not be the case at all. But it is certainly a possibility and would be completely idiotic to not inform Pioneer of this issue.