The necessity to have to had a dramatic redesign of phone models and variations every year is the backbone MO of Nokia, Motorola, Sony et al. It does not or paid too much by Apple. Form and function is the foremost in Apple's mind not how it looks. If it works well, it does not have to be evolutionarily redesign to succeed. Much to the dismay of folks like DaHarder et al. with their strong Android, Nokia beliefs. Sorry for you.. just walk away.
Jonathan Ive disagrees.
I agree that function is the top priority, but Ive's position and power in the company shows that appearance is very important to Apple too.