At this time, the Sony Xperia X10 currently runs an outdated version of Android 1.6. A lot of people have been wanting to get the 2.1 update because it supports multi-touch and other services that are exclusive to 2.1. Today, the people at Sony has confirmed that the Android 2.1 update is coming around September. I believe that this update is compatible with the unlocked and AT&T versions of the X10.