I agree with the above comments saying that a minority would want it, but I seem to use the numeric keypad all the time as a programmer or calculating pixels when I'm doing layout work. I really disliked the minimal keyboard that came with my 27" quad core iMac, so I took the free upgrade. Its unfortunate you can't do that with a notebook.
If you're like me, half the time (at the very minimal), you'll be using your laptop at home on a desk. Personally I use the bluetooth apple wireless keyboard (exact size as the laptop keyboard with no numpad) BUT I also own the full size keyboard from apple. You should shell out for some money on this if it helps you do work and when you're on the go, it's unlikely you'll be actively needing the numpad.
