i have two iphones, 2g & 3g on a family plan w/ no data. got the iphones used and i'm out of contract but still with att. i LOVE the lower cost of the monthly bill, especially while everything else(cost of living) risen/rising.
i love my iphone and so does the wife. it's a phone, ipod, camera(video w/ cyorder), media player, mobile gaming device all in ONE package. i have constant access to the internet home and at work, and that's the two only place i'd ever need it. i cannot justify the extra $50 on top of the voice plan, my life just doesn't require it.
my .02