CK Prahalad was a remarkable person and his loss is felt by many. He was a true friend — when he was your friend. Lately he was a true friend of India. His work about India is remarkable. One of the best lectures by him was earlier this year as Palkhivala Lecture in which he articulated challenges faced by India in very constructive way.
A very good tribute to CK is written by Neelima Mahajan in Forbes India. This article has a good coverage — except one minor misunderstanding resulting in a slightly wrong quote about returning wine — of my interactions and relationship with him.