With postpaid prices only going up, and a number of MVNOs jumping into the prepaid market(omg, causing competition *GASP* sort of), its not wonder people are ditching postpaid and going pre-paid. Look at it this way: Post paid for an Iphone4 on AT&T runs about 90 per month with 2GB of data. Prepaid for "unlimited" data on some carriers can get as low as $40 per month. Seriously, with the economy in a slump, this really isnt a surprising shift.