spec vs spec matching gonna work if they both on same platform. Lets say HTC One X vs Galaxy Siii both on android.
Even on spec to spec they can say iphone 5 weigh less, can be used with one hand, highest resolution on small display, better design and made with luxury craftsmanship, better apps store with more quality etc..
For some of other siii specs apple can say do you want a small one hand usable phone or tablet like 2 hand phone. Apple has done a great job packing all that to such a small usable device and even offering it smaller and lighter than 4S.
So i think iPhone 5 is a better balance of technology and usability of a everyday phone over Galaxy Siii.
I don't think normal smartphone buyer looking so hardcore on the specs. Most of them go for looks, features or usability. I think both of them plus HTC One X etc.. have all the same features packed. So for the mass its advertising which will sell the phone.
Personally i don't have nothing big to gain from new phones. Old iPhone 4, Galaxy S2 will do the same work without a glitch. But like to switch to a Nokia Windows phone 8 device. Will see..