Whilst there's not much point speculating the CPU, we know it will be faster than the 3GS as the latter was said not to be able to run certain functions of the iPhone 4.0. I'm betting the same CPU as 3GS without the underclocking, plus a new GPU.
Larger battery allowed by increased width and height of unit.
Slightly reduced depth with a flatter back made of matte aluminium (yes, despite signal issues) [I think this is also indicated by the silver-wash of the homescreen when in multi-task managing mode] or glass
Same rounded corner design.
Screen resolution 640x480 (yes, unfortunately new ratio, bring in line with iPad)
Capacities: 16, 32.. perhaps a 64GB at a later point or immediately with massively inflated price
2 extra dedicated buttons on side: 1) old home button functionality 2) screen rotation lock
2mp front facing camera.
5mp back facing camera + LED flash
Larger battery allowed by increased width and height of unit.
Slightly reduced depth with a flatter back made of matte aluminium (yes, despite signal issues) [I think this is also indicated by the silver-wash of the homescreen when in multi-task managing mode] or glass
Same rounded corner design.
Screen resolution 640x480 (yes, unfortunately new ratio, bring in line with iPad)
Capacities: 16, 32.. perhaps a 64GB at a later point or immediately with massively inflated price
2 extra dedicated buttons on side: 1) old home button functionality 2) screen rotation lock
2mp front facing camera.
5mp back facing camera + LED flash