I reckon all Toyota can do is outgun Nissan in another direction. i.e. create a monster mid-mounted V8 RWD Lambo eater. They seem to be heading down that path from the YouTube videos of the next Supra (i think it was a V8/V10?)
They will be wasting their time trying to take Nissan's customers. Everyone's wrapped by the GTR, plus the media campaign for it was so strong Toyota will have a very hard time convincing the world to get a 21st century Supra.
Also i don't totally buy the article's comment that Toyota HAS to beat the GTR or it'll be a failure. It only needs to keep up, make strong sales, and cater for a global market. They're already going to have an affluent, niche customer base with their wanky 'F1 inspired' Lexus punchline. And even by milking the Lexus badge as their ultra-performance model also shows they're conscious of PR, niche markets and providing what the GTR lacks (an aura of class). Lexus hasn't got a strong racing heritage like GTR or Ferrari does, so they're using the Lexus brand to provide theat 'glow' which makes us go wild for 'GTR'.
GTR is an all-rounder. Toyota will probably look into an exotic supercar with a premium price tag. That's where i'm putting my money.