Because it is late. The sony Ericsson officials told the reason that they are having a lot of orders for Sony Xperia S devices but the shippment of the mobile phones getting late that’s why all the people who pre-order the xperis S so they have to wait a little more to get the phone in their pockets. Another reason is that its shipping will be started at the mobile conference. But you have no need to get worry because the new date for the shippment is 13th Febrauary and this time it will be confirm. On theother hand another UK retailer Clove announced on their official website that the sim-free version of Sony Xperia S will be available at their website for sale in the first week of March 2012. So if you have not pre-order your Xperia S yet and want to get a sim-free version then you have to wait till march 2012.