Price of the phones starts from $649 for 16GB and goes up to $849 for 64GB version. These unlocked phones are free from monthly contracts, works on any GSM network around the globe. Sorry CDMA networks, unlocked iPhone 4S is not yet ready for you!
Its a good move from Apple. This helps people from staying away from multi-year contracts and also visitors returning from USA now can buy an original unlocked iPhone to use in their home countries.