somkun:
but I didn't know if Arduino was capable of managing a <70 key keyboard, and if so, could I have a fn key that changed the use of certain keys? (i.e. fn+1=f1) Also what would muti-press limitations be?
Yes, you can use Arduino to make a full sized keyboard. I've helped a couple of people accomplish just that. The keypad library Arduino Playground - HomePage has default support for a 10x16 (160 key) keyboard.
Multi-press will have a problem called ghosting. That means if you press 3 keys in a triangle then a fourth key will also appear to be pressed. Release any one of the 3 keys and the ghost will go away too. Ghosting is normally solved by using individual series diodes with each key.