My guess is they went with EDGE because nobody's made a small-enough 3G chipset that gets decent battery life for them to use. From what I've read, the only slim 3G smartphone out now (the BlackJack) has bad enough battery life that it ships with two batteries.You do realize EDGE speeds in practice are barely better than dial-up?
I bet they went with EDGE to keep down the monthly fee.
True broadband access over cellular would probably double the monthly fee ($60/month w/ a voice plan for Verizon EVDO).
On Verizon, if you have a smartphone like the iPhone, unlimited EVDO should only be $40/month (unless you're using it as a modem).