They did a segment on this last weekend, the Austin circuit isn't even built yet. It looked as if this was as far as they have got with it
http://motoren.files.wordpress.com/2011/04/austin-circuit-1.jpg
as for the NJ race, will they get permission? doubtful. Perhaps I'm wrong but I don't think it will take off in the US, americans are conditioned for that driving around in a circle approach.
First job for F1 is to reign Red Bull back into the pack, allowing Vettel to get away like that is ruining the sport.