If you're dead-set on an iPhone, I'd wait until they've had time to fix all the issues from their initial release. Don't be an unpaid beta-tester.
The last time we upgraded, we went with Android. We've had our AT&T Android Inspires for roughly two years, and we're almost ready to upgrade out of frustration. I didn't want to jump on the Apple bandwagon, but I was very irritated with Android's horrendous battery-life (Utilizing battery power is one thing that Apple has down to a science.). Also, we recently had a software upgrade that changed the operating system's appearance (and now treats the phone as if it's a Desire instead of an Inspire.). Since the upgrade, I've found myself having to restart the phone more frequently and do hard-resets more frequently. Also, as far as making calls, I've always had problems with this phone echoing my voice, or not transmitting my voice to the other caller (I can hear them, but they can't hear me.). This phone issue also cost us a potentially lucrative deal when we tried to make an offer on a house to a seller who got frustrated and angry after ten repeated calls that got dropped.
I realize I'm digressing to my own personal experience. I've heard good things from coworkers regarding the Galaxy, but Apple has consistently made decent products (after fixing initial bugs.). Also, the Apple Maps fiasco should be something to consider if you plan on using the navigation feature.
If you're more tech-oriented, Android may be the way to go, since there's less restrictions on customization, but if not, Apple may be the way to go, for ease of use, as well as the fact that the Apple store heavily restricts what apps it will allow (protects you from malware.), while Google Play is pretty much unregulated.
