Was this a great release compared to previous iPhones? Absolutely. You can't complain about that.
Was this a great release compared to OTHER smartphones? No. Not at all. Nothing revolutionary here.
So, if you're committed to the iPhone, I think you'll love the new one. If you're open to using other phones, well...might want to look elsewhere.
Personally, I LOVE the look of the iPhone 5. I think it looks amazing, and the materials used are fantastic. Feature wise, I'm drawn to the Samsung Galaxy S III. I've owned the original iPhone, iPhone 3G, and iPhone 4, but am now thinking it might be time to try something different. Removable battery, upgradable storage, and a nice large screen are the major differences of the SIII over the iPhone for me.
But god damn if the S III isn't the ugliest thing around. And plastic? Bleh. That might be enough for me to stick with Apple (not to mention the amount of $ I've invested in their ecosystem via Apps...they kinda got me by the short ones there).
Choices, choices. Amazon has the SIII for $99 right now, too...hmm....