I wouldn't turn you away from the Samsung S3 as I think it is a great device. I stuck with the iPhone 5 due to laziness because I know the Itunes/IOS environment well, but it was still a close decision.

But I am sure that the same functionality that we used to have in IOS 5 will get reproduced in IOS6, either through Apple fixing their maps or someone else integrating their Maps app into IOS 6.