The idea of the Xperia device was good. Touch screen gaming is pretty weak overall. The thought of a controller being built right in seemed like a great fit. Unfortunately, they didn't execute very well with that idea.
The device is underpowered compared to the other Android phones. A majority of the playstation content is only compatible with the phone. IE: content you buy for your PS3 minis, PSP doesn't work on the phone.
Instead of a new Xperia, I'd rather see support for blue tooth controllers to be added into Android. Then maybe someone can make a shell of a controller to fit your phone into. Portable gaming achieved.