Exciting news if you’re a fan of Sony’s Xperia designs, but not the huge displays that seem to permeate the mobile world these days: the Sony Xperia U (also known as the Kumquat/st25i) has been spotted in its first set of leaked photos. It’s getting comfy with Sony’s new international flagship, the Xperia S, in a series of shots found by Android HD Blog (Italian). Both phones share a lot of design DNA, but it looks like the Xperia U is much smaller, with a screen somewhere in the ballpark of 3.2 inches. Like the S, the Xperia U is still running Gingerbread.

The similarities between the S and the U don’t end at the manufacturer label – in fact, they don’t even start there, since the U is using the now outdated “Sony Ericsson” label. It’s got the same attractively blocky shape as the Xperia S and the same see-through capacitive navigation area – a fetching feature that didn’t make it into the Xperia S’s US cousin, the Xperia Ion for AT&T. It keeps the slightly beveled back basic button layout, with a black plastic shell oposite the Xperia S’s white – both phones will probably come in both colors. A removable 1290mAh battery hangs out in the back compartment.

What you’re looking at is probably prototype hardware, though it seems complete enough that this is likely a near-production design. There’s not much information on the specifications beyond the previously-leaked 1Ghz dual-core processor. Note the side-loading SIM card slot, similar to a DROID RAZR or HTC Legend. It’s almost certain that we’ll see the Xperia U at Mobile World Congress next week, so keep an eye on Android Community’s MWC 2012 portal for all the juicy details.