Two questions about the Sprint iPhone

[fmgtech]

rgG wrote:
Sprint and Verizon do not use SIM cards, so if you needed to switch from Sprint to Verizon, you would need to switch phones.

I have been told that Sprint roams on Verizon, so it might be possible that you could roam while at your vacation house, but I think there are limits on how much roaming Sprint will allow.

I don't know about tethering.

I thought the new iPhone 4S was supposed to be a world phone, meaning it would work on AT&T, Verizon, or Sprint?