Diesel . . .
VW has dropped diesels in the US for 2007. They may be back in a couple of years, who knows? Instead, they'd like to sell you a big 2.5 liter five-cylinder gas engine in the Rabbit and Jetta. The diesels probably get 50% better mileage, but VW is very, very interested in trying to compete tit for tat with the Japanese makes and since they don't offer diesels here, VW would just as soon simplify things and forget about the diesel market. They had already dropped the diesels down to 45-state status in '04. Even in '02, when I bought mine, many dealerships didn't stock any diesels, and those that did often only had a handful.
After years of refusing to make any diesels at all, Honda recently introduced some in the European market. From all reports, they are excellent, although that isn't a total surprise given Honda's tremendous expertise in combustion technology. They are probably the best placed to meet stringent future particulate limits here in the US. If they do decided to bring them over, it will make an interesting incentive for VW and other companies to think again about small diesels here.