I used to run karaoke at a place not too far from ESPN, and we occasionally got visitors from the network at the venue. I got the opportunity to meet John once-- he had come in with Chris Berman-- and he was as genuine and personable to meet as I found him to be on the air.
John was a staple at ESPN, and I recall how versatile he was. Very knowledgeable person.
My condolences to his family, his friends, and his colleagues. He will be missed.