Typical Snopes: “Second, we found no evidence of U.S. government regulations that would prohibit the sale of automobiles such as the referenced Volkswagen Passat in the United states solely because of their mileage ratings.”
Nope, Diesel passenger cars are banned here for more than that reason alone. BUT most diesel passenger cars are indeed banned here and you cannot buy the diesel Passat with its 62 mpg (using US gallons). Note that Snopes does not claim that the cars are available here, which is the point of the video and emails. Snopes should say TRUE- this car cannot be purchased here.
I found this- Diesel passenger cars are indeed available, and more will be available in 2013, but not with the same technology as the Passat mentioned in the thread.
http://www.edmunds.com/diesel/before-buy.html
Just saw one on the road today.