This is really a nice christmas gift! Apple is going to release iPhone 4S coming in November 2011.
16 GB for $649,
32GB for $749,
64GB for $849
The unlocked iPhone includes all the features of iPhone but without a contract commitment. You can activate and use it on the supported GSM wireless network of your choice, such as AT&T in the United States.
* The unlocked
If you don’t want a multiyear service contract or if you prefer to use a local carrier when traveling abroad, the unlocked iPhone is the best choice. It arrives without a micro-SIM card, so you’ll need an active micro-SIM card from any supported GSM carrier worldwide. To start using it, simply insert the micro-SIM card into the slot on your iPhone and turn it on by pressing and holding the On/Off button for a few seconds. Then follow the onscreen instructions to set up your iPhone.
Source from >> http://store.apple.com/us/browse/home/shop_iphone/family/iphone/iphone4/about_unlocked?mco=MjYwMDIyNTg