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....