Speculation is also rife about the leading man: first it was Saif Ali Khan, who later moved out because he wanted Vishal to do a film for him in return (which Vishal declined). Apparently, Abhay Deol was to replace him, but now SAK is back. It's borderline gossip, so just read this news item instead.
The film is slated to be a smaller, more experimental film. Here's an interview with art director Samir Chanda on some of the pre-production work happening in Kolkata. Incidentally, he says the story has been written by Mukul Sharma. If I'm not mistaken, this is the same MS who writes for the Times of India on topics such as science and spirituality, used to run the popular Mindsport column during the bearable days of the TOI, and is the father of Konkona Sen Sharma (who, but for her pregnancy, should have been a shoo-in for the 2nd lead's role).