Apple's following the exact same playbook they wrote with the imac and ipod where they focussed heavily on the primary form factor for several years and then threw open the gates to colors.
I have a Nokia 3210 as backup phone which still works flawless today. Or an E-7, still working. Most of the other phones I had went defunct at some point or the non-replaceable battery went dead and new phone was cheaper than getting it replaced and so on. Thats something to be proud of. Ok, maybe not for the product managers ;)
http://www.fastcodesign.com/3017050/untold-stories-inside-ap...