I can see the merits of both camps...
A) Some folks like to do stuff with the extra space
B) It's nice having nothing else there, as to better isolate the spacebar key, and home button/gesture area, as they are 2 important and commonly used elements
Perhaps an iOS update that gave users the option to toggle which one that like could be in order?
.
That said, I'm still amused how the keyboard in alphabet mode/view couldn't fit in an extra row for numbers, and find a way to squeeze just 1 key to either side... one for ',', and another for '.'. 2 commonly used characters in typing. It took a while for me to get used to using comma, period, and numbers without switching to "number mode/view" on my phone, but it was a nice change.