It looks like this issue was caused by Apple mistakenly marking the centre of Local Government Areas as 'cities', in Australia at least. See example at http://imgur.com/qlciM for an example from Perth; Cambridge and Vincent aren't suburbs, and the others are in the wrong spot (Joondalup CBD is on the wrong side of the freeway)
A more glaring issue with Apple's map of Perth to my mind is that Fremantle Harbour has been completely filled in. See the bottom left of this Google map for comparison: http://i.imgur.com/GsmxQ.jpg
