Not sure if India has seen such strong leadership since Mahatma Gandhi's salt satyagraha (which was a "war" strategy that eventually led to India's independence).
India has a history of corruption across the board: not just in government (as most Indians would like to say), but in business, education, even religious institutions. A culture of corruption is one of the basic reasons why India has remained mostly a backward country (a substantial percentage of Indians do not even have electricity and toilets).
If Modi could close any loopholes and keep the threat of repeating this move once new currency is introduced, India could change for the better. I look forward to this change!