After test driving the Yaris and Honda Fit, the peppy engine, higher seating, amazing standard safety features and overall appearance sold me on the xD. My only real complaint is the road noise, but that's of pretty minor importance to me. It's a tight little, precise ride and the manufacturing tolerances are really impressive. Everything feels like quality on the Scion, unlike with the Ford Focus that it's replacing. I also love the firmness of the seats. The toggle feature on the l.e.d. odometer which allows you to see your mpg at any current moment is really nifty (although I'm a little suspicious of the accuracy of such a device). At any rate, this is an exciting little car.
The high seats, extra peppy engine, great mpg, I-pod jack, and standard side curtain airbags.
Better noise insulation, greater rear window visibility & more front seat leg room.