I want to upgrade to the iPhone 4S for a couple of reasons: mostly Siri and camera, however I'm not eligible to upgrade from my 4 until Feb. Next year. That being said, since the 4S is a world phone and is versatile in the sense that it's the same phone that can be used on either CDMA or GSM networks, would it be possible to upgrade to the 4S on a Verizon plan (who is eligible to upgrade), and then switch the phone to AT&T to replace my current 4? Just an idea that came into my head after thinking how to get the 4S ASAP. Other option would be buying it with no contract... But who knows if they'll let those people preorder. Plus, saving a new hundred dollars doesn't sound so bad either What do you guys think?