I am very please with my Yaris. It is a manual tranny, and like others have said, get the manual if you want to make the car fun to drive. Mileage is awesome. I get 47 MPG in the warm season. It drops to about 41 in the winter. I do not baby the car to get that MPG. I accelerate to keep up with others, and usually drive +7 to 10 MPH over the limit. The brakes are solid, the electronic steering is solid, the suspension does not roll when taking corners at 30 MPH! The radio sounds great, the lights are very bright...I can't really find a fault with the car. The one thing that could be better are the front seats. My lower back tends to sink into the backrest too far.
MPG. Stick shift. Looks. Build Quality. Simple yet snazzy. Easy to work on. Can almost change the oil filter without going under the car. Inexpensive. Where else can you get a great car like this for under $15k new?
Seats could use help. A 6th gear would be great, as running the engine at over 3k at 70 mph seems too high. Stock tires wear out quickly (potenzas), but they do stick to the road in the turns...