I'd actually like to see a slightly bigger form factor in addition to the 4/4S size.
The new form factor has been compared to a bar of soap.
As I've posted before, the form factors are for completely different things.
I think some of it is, like, really good form factor.
How do I craft a form factor to meet their needs?
There are many combinations of form factors and device families.
Why bother spending more money (and perhaps power) on an i7 in this form factor.
The biggest impact could be seen in the form factor of credit cards.
For a comparison of form factors, past and present, check out Motherboards.org.
There isn't much more that can be done with the smaller form factors.