What if, instead of iPhone 5 or iPhone 4S, Apple decided to call the new device iPhone 4GS? Confession: I used to love those old Marvel What If? comics, like what if Captain America were discovered today, or what if Conan appeared in the 20th century, or what if Jean Grey didn't die? (You know, before they retconned that into reality.)
So let's pretend for a moment that there's no big new redesign this year and that means Apple doesn't want to go with iPhone 5 as the name, and iPhone 4S just doesn't do it for carriers who, now touting HPSA+ as 4G are eager to slap that faux-logo on every box they can. AT&T and others would almost certainly want to market an HSPA+ iPhone as 4G, the way they do their other HSPA+ phones, so having 4G or 4GS in the name would be perfect for them.
Of course, Verizon (and potentially Sprint) don't have HSPA+ networks, and the new iPhone likely won't support LTE 4G until next year. That would leave Verizon at a significant marketing disadvantage. Would Apple be willing to do that to Verizon? Either before or after Verizon took Samsung's side in the ongoing Apple vs. Samsung patent dispute?
That's the problem with "what if" speculation -- it can get out of hand quickly. iPhone 5. iPhone 4S. iPhone 4GS. iPhone 4G. Anything is possible when no product has even been announced yet -- and no announcement has even been officially announced yet.
Personally, iPhone 3GS always sounded un-Apple-like to me -- like a way to recover and get back on the generational tract. I can't see them going with iPhone 4GS unless they're backed into a similar branding corner, but would it make sense, given the HSPA+ carriers, to have 4G in the name?