Today was just surfing GSMArena, read about Xperia U and did a bit of comparison between SONY Xperia U and HTC One V. Xperia U is a winner for me any day:
-Lighter in weight (Xperia= 110g, OneV= 115g)
-LED backlit LCD display
-280 ppi pixel density
-Scratch resistant glass
-Secondary front facing camera
-Dual core processor
-Removable battery
-A little cheaper as well
On the other hand, One V has its plus points too like a bigger screen (just 0.2 inches more), memory card support and ICS out of the box.
Points where both stand equal are Camera, build quality, Audio (HTC with beats audio while Sony with 3D surround sound) and RAM (512 MB).
So people who are thinking about buying One V must give Xperia U a serious thought!