According to Automotive News, Tata says that it could bring the Nano to the U.S. as soon as 2011 or 2012. However, you can bet your bottom rupee that it won't cost $2000, won't weigh 1300lb, and probably won't get 61mpg.
Before Tata can sell the thing in the U.S., it must be fitted with "2.5mph" bumpers front and rear.
It will need ABS and stability control.
It will need front and side airbags.
It will need front, rear, and side impact crash structures so it will get a decent score on NHTSA's crash tests.
It will need properly formulated catalytic converters to meet tough emissions standards.
It will need an automatic transmission, since we Americans are forgetting how to shift our own gears.
When these and perhaps other features I have not thought about have been added, it will likely cost more than the $6000 or so that the Tata Europe is expected to cost.
Suppose it comes in at an industry leading price of $7,500. That's great for a new car, but in 2012 you could probably get a nice used compact or mid-sized car of the 2007-2009 vintage for that kind of money. Nothing exciting, but a solid reliable ride. With amenities such as power locks and windows, decent radios, an opening trunk, dual wipers, fold down seats, and so on.