Will it be the iPhone 4GS or iPhone 5?
Either way I am ordering it the day it ships,

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Funny enough, recently i've been seeing more articles coined "iPhone 5" than the iPhone 4S and iPhone 4GS garbage.
Obviously it's the 5th Generation iPhone, and so iPhone 5 is the best suited name until the official name is released.
iPhone = iPhone 1
iPhone 3G = iPhone 2
iPhone 3Gs = iPhone 3
iPhone 4 = iPhone 4
iPhone 5 = iPhone 5
iPhone 6 = iPhone 6
or..
iPhone 4S = iPhone 5?
iPhone 5 = iPhone 6?
The iPhone 3GS was more of a placeholder as a name, because marketing wise, consumers want to see more in the product than less. So it wouldn't make sense to go from iPhone 3G to iPhone 3.
The iPhone 4S term was coined by some random developer who was testing out an iPhone 4 with a Dual Core A5 chip for their app, and a lot of people blew it out of proportion.
Also, all the iPhone 4 owners who are filled with buyers remorse want the next iPhone to be a minimal upgrade to still feel 'new'.
Also..
A4 chip, iOS 4, 4th generation iPhone = iPhone 4
A5 chip, iOS 5, 5th generation iPhone = probably iPhone 5