The wikipedia page for the top gear laps has a note next to the GTR laptime squibbling about the GT-R they tested being JDM something or other.. So there might be enough in the version that'll make it to the US/UK to take 6th place from the Atom. I think the vspec due in a year or two will get 7/10ths out of this lap and could probably beat the Maserati, too.
The regular model they lapped this weekend sure looked capable, but if Jackson's comment about the track being power-biased is true, the ZR1 ought to be competitive, too.