Apple has said it has never tracked iPhone users. Well... it might have tracked them a little bit, but there's no harm done. Well... when it says 'no harm done' it means 'not much harm done', certainly not enough to change the way it is... erm, not tracking anyone. But it's changing the way it doesn't ever track anyone just a little bit just in case.
Not because it's been caught spying on you, you understand. It was gonna change it anyway, honest. It certainly has nothing to do with an unpleasant media backlash or questions being asked in congress or anything like that. Honest.
Even so, Apple will soon release two iOS updates which will limit the size of the database and automatically encrypt it away from prying eyes.
Here's Apple's take on the matter in full: