I'd put the GTR alongside the 911 turbo in a sports cars category. They don't have the figures, they dont have the exclusivity or the price tag to call them supercars. Maybe they can keep up for a few laps on the topgear track, but that alone doesn't make any car a supercar. If I build a Z that can run a few tenths off the Enzo's time, I still don't have a supercar. Supercars to me are Murcielagos, Enzos, SLR's, K-eggs, Carrera GTs, Zondas, McLaren F1's. Do you honestly thing the GT-R belongs in that group?
And I mean this in just a respectful manner, I love the GT-R don't get me wrong. The GT-R is a supercar slayer, but not a supercar itself.
And just so you see I come in peace, here's some eye candy for everyone. Gemballa released a Carbon-laden version of their mirage gt back in june.