Well the obvious difference is clearly the four corner UI.. which doesn't seem like Android at all, but is quite clever and useful. I prefer the ADW launcher, because I felt that the default UI didn't really give the feel of Android. Also, how deeply has the system been tweaked? As in, many Android handsets can be rooted and highly customised, although the X10 Mini cannot load ROM's, due to having no apparent recovery mode, which means custom system files cannot be flashed due to system files already being used (obviously as the phone is running). So does anybody know how different the X10 Mini's Android setup is from most other handsets?