Fast forward almost a year into the future and we have a USPTO trademark filing by Sony Mobile hinting that the Xperia Duo might be real after all. The trademark was filed under "Mobile phones and accessories for mobile phones", and the filing itself is dated March 28.
Sadly, the trademark filing for the "XPERIA DUO" name does not give out any clues whatsoever as to what kind of smartphone we are dealing with. It might be a device reminiscent to the one that leaked last year, or it could be an entirely new design. One thing is pretty certain, however, namely that if the rumored Sony Xperia Duo ever materializes, it will sport a dual-core processor. The remainder of its hardware specs are anyone guess right now, but if the device is real indeed, the rumor mill will probably start filling in the blanks pretty soon.