If you're seeking a difference between 2007 and the 2008 Audi A8, performance is where you'll find it.
The 2008 Audi A8 uses a 4.2-liter V-8 to churn out 350 hp, though a 450-hp W-12 engine is fitted to the A8 L W12.
The V-8 offers an extra 20 hp this year, says Automobile, as well as an extra 15 pound-feet of low-end torque. Audi says the A8 can hit 62 mph about 6 seconds and can reach a top speed of 155 mph. The V-8 engine "gives up little to the V-12" according to Motor Trend, and delivers 18 mpg highway.
Both versions of the A8 use a 6-speed automatic. Forbes Autos says it can be "taken through the gears like a manual." Cars.com says "considerable downshifting occurs on even moderate upgrades," but it has no qualms with the shifts themselves.
The A8's retuned steering and air suspension could use more work. The suspension can "induce unsettling wallow when at softer settings," ConsumerGuideAuto says. Cars.com instead found the full-size sedan "stays beautifully flat while cornering and responds immediately to driver inputs." Motor Trend likes the steering's "perfect feel and weight."