The model, mated to a V6 2.8 TSI good for 210 hp and 280 Nm of torque (about 206 lb-ft.) has a top speed (but only for German Autobahn) of 238 km/h (about 150 mph) and does 0 to 60 mph in 8.0 seconds. As per the green specs, sorry: 8.3 l/100 km as "standard consumption" (I guess EU's combined cycle) which are equivalent to 28 MPG. CO2 emissions are a respectable 199 CO2 g/km.
Just in sake of comparison, the Lexus 600h (UK specs) has a bigger 5.0l V8 engine that has 290 ponies under the hood and 520 Nm of torque (384 lb-ft) yet still runs with 9.3 l/100 km (25 MPG) and 219 CO2 g/km.
Lightweight materials, such as aluminium, are the key for the relatively low weight of the car (1690 kg or 3725 lb). Audi has also enhanced aerodynamics to reduce the air drag coeficient. The engine uses TSI direct injection of gasoline, plus variable lift (valvelift). According to Audi's definition "Valvelift uses sliding cam units mounted on the intake camshaft, which are moved by an electronic control mechanism. Depending on the engine power demand, the valves are opened wide or less wide as determined by the position of the cam units."