With, Mani Ratnam and Ambanis refusing that Guru is based on Dhirubhai's life, lets hunt for the truth by finding what Netizen are thinking.
Post movie Guru's release the activity in Wikipedia has increased significantly. Check this small analysis on the number of entries happening in Dhirubhai's wikipedia entry. You will find small dips after 20th Jan, this is because most entries happen on Saturday/Sunday than weekdays. Weekend free time! Is this is a general trend, that most entries in Wikipedia happens on weekends? Will leave that analysis to others.