In short: iPhone 5 requires iTunes 10.7 or later iTunes requires OSX 10.6.8 or later So, if you are still on Leopard, you can't actually sync an iPhone 5 to your computer, because you won't be able to download the latest version of iTunes. I found this out when I tried to set up a friend's new iPhone 5 from a backup she had on her macbook pro running Leopard. I was able to get her up and running by backing her phone up on my Mountain Lion mac, but the fact remains that she can never sync her phone to her own computer without upgrading the OS. Has anyone else run into this issue? I haven't heard much noise around it, and from what I understand there is no workaround. I have two reasons for posting this: 1) to see if anyone has hacked together a workaround and 2) to make those still on the fence, or even waiting on their pre-order, aware of something that is clearly stated in the system requirements, but not widely publicized -- namely that you may not be able to sync your iPhone to your mac without a system or even hardware (for PowerPC users) upgrade.