I feel that this topic should be a poll of all macrumors users.
Before voting, take a look at this picture, comparing the iPhone to the HD2 which offers a whopping 4.3" screen size, and yet manages to be approximately the same size and weight as the iPhone, all while offering superior battery life!
Posted by iPhonedHome.
From my experience, it's far easier to use the on screen keyboard, browse online, read pdfs, emails and e-books, and watch movies with an extra inch of diagonal real estate. Everything just looks nicer, especially games, websites read easier when the text isn't quite so tiny, and movies feel more immersive. It's shocking how big a difference that extra inch makes.
The front of the phone could made more akin to this...
or this...
It's not the thinness of these phone designs that is impressive, it's the manner in which the designs maximized the amount of screen space on the front of the phones.
Apple could continue to sell/manufacture the 2010 iPhone HD/4G for $99 for people who want that, and manufacture a 4" - 4.5" inch screen alongside it priced at $199 or $299 for everyone else.
Going with this size would also give Apple the room to incorporate a slightly bigger battery and thus actually would improve the battery life.
The numbers are there for any one to judge. 56% of the people here want a 4.5 inch screen, 38% do not. In otherwords, for every 4 people that don't want it, 6 people do. That's is a significant majority. And I'm certain the poll would be even more lopsided if it asked how many people wanted a 4" screen on the next iPhone.
No, this forum doesn't have ALL iPhone users. But what this forum has are the biggest most passionate apple customers and users, the users that not only buy apple products but go out and convince friends and family members to buy apple products. In short, this is a base of people that apple does care about, or at the very least should.
It's not only tech geeks that enjoy watching videos on the iPhone, browsing the web on the iPhone, reading ebooks on the iPhone, reading maps on the iPhone, looking at and showing off pics on the iPhone, all tasks that are made substantially easier with a bigger screen. I am willing to bet that a general sample of all iPhone owners would show similar stats, with most wanting a bigger screen that makes these tasks easier and more pleasent.
In fact the bias on this forum if anything tilts the other way. Lots of apple fanboys post here, and they insist that every decision made by apple should be kept as is, since the first iPhone had a 3.5" screen and a large bezel, all iPhones should forever have a 3.5" screen and a large bezel they argue. In addition, elderly people don't post here, but they do own a substantial number of iPhones. And they need and desire bigger screens that are easier to see and do tasks on more than anyone. The new Nintendo DS XL, the one with the massive screen, was marketed entirely to the elderly population that didn't just want but actually NEEDED a bigger screen. And it sold out faster than any other gaming device to date. So clearly a demand for this is there.
Like I said, apple has recently started to offer last years model of iPhone for sale alongside the current iPhone. There is no reason they wouldn't or could offer a slightly updated version of the 2010 iPhone HD with it's 3.5 inch screen for sale for that 38% while offering the 4.3-4.5 inch iPhone for the rest of use.