Apple considers these to be private APIs, and they also got games developer Storm8 in trouble earlier this week; their games were pulled from the store in response to a lawsuit alleging that they were collecting data from users without their knowledge.
Chillingo, publishers of Ravensword, contacted us about this story, and they said that while the Unity engine does allow developers to use these calls, they did not use them or collect any user information. We're also told that the problem APIs "have been removed," and Chillingo has resubmitted the game for App Store approval.
As I understand it, this is the same type of issue that came up with Google a while back. It's not the same APIs (Google was using the proximity sensor back then), but now as then, it's Apple's call whether they will allow developers to use these private and undocumented calls. Obviously some apps on the iPhone have to access the address book from time to time, but it's Apple's call whether they can use APIs like that or not. This time, it appears, they said no.
Update: Unity has also contacted us, and they say that the engine was updated to Apple's wishes as soon as they learned of the issue. They also would like to point out that while Storm8 did use the same private API calls, they don't use Unity to run their games. Storm8's update on the issue is here.