I would never buy a diesel Corolla just because of the noise.I hear diesel trucks and they sound like they are not running right (too much ticking).
Diesel fuel is more expensive than regular unleaded.
I'm the other way around. I think diesel engines sound cool. They sound like real engines. I make my living driving a Paratransit bus which is based on a Ford E-450 Super Duty DRW chassis, powered by a 7.3 liter PowerStroke diesel engine. Quite frankly, I don't really get an impression of the engine as being objectionably noisy. Yes, it's loud, but not ear-splitting. My bus is a 2002 model; the 2004 and later buses have the new PowerStroke 6.0 diesel and a 5-speed auto, as opposed to the 4-speed in mine. This engine/transmission combo is an order of magnitude noiser, particularly at idle. The damn thing sounds like every internal bolt is coming loose. The injector pump has a really annoying rattle. The 5-speed transmission gives a neck-snapping lurch when shifting up through 2nd and 3rd gears. This is a motor with some serious issues -- I hope Ford goes back to the 7.3 liter design ASAP.
One of the guys I work with has a diesel Passat, and my neighbor a couple doors down has a diesel Jetta. Those neat little TDI's just purr along -- not at all noisy. I test-drove a TDI Jetta before I bought my first Corolla, and I was very impressed with it. I particularly liked the immediate application of high torque at low RPM -- the car accelerated effortlessly, with well-spaced gear changes which resulted in meaningful acceleration, no lagging. To this day, I think I should ahve bought the Jetta -- except for the fact that a friend of mine owned a gasoline-powered Jetta and was having major reliability issues.
The challenge for Toyota in introducing a diesel to the U.S. market will be one of producing them fast enough to meet the high demand, while maintaining their quality levels. I think they'll fly off the lots, and would command premium prices -- unfortunately!