There’s NO unlock for the baseband firmware in iOS 4.1 update. However, it is possible to jailbreak iPhone 4, update it with iOS 4.1 and still enjoy the software unlock. How? Here’s a method where you can retain the older baseband, update your iPhone 4 with iOS 4.1 and use the ultrasn0w unlock.This guide is meant for users on Windows as well as Mac platform.
Apple to offer CDMA iPhone via Verizon
After much ado, Apple finally gives in to develop CDMA iPhone for Verizon Wireless. However, Verizon will work to introduce some stopgap technology for that. While Apple will continue working on its annual product cycle.