It's official now, 2012 GTR is going on sale, in Japan, starting 24th of November, UK is expected somewhere early 2012.
Noticeable changes are in power, now features 550HP, lower emissions, new aerodynamics, new suspension systems, lighter wheels and improved exhaust.
Also, rumors say that Nissan is building a more track focused model, but only RHD(that means Japan and UK).
More information will be available in December 2011.
Edit: Video added.