Need advice-deciding between i-phone 3G and Blackberry Curve but hesitate changing from Verizon to AT&T?

Currently have a PDA where I have struggled with functionality (phone and battery in particular). Know the Curve will be great and service will be good. Have been wanting the 3G, but worried that I will be giving up some practical functionality (battery, coverage, etc.) for the coolness. Primary use is e-mail and phone. Need perspective....