Sad to see this news. I grew up on Johnny Carson and Ed McMahon, and they were a big part of my childhood. I always identified with Johnny Carson, as an introverted person in "real life" who found a home in the media, and I always enjoyed his relationship with Ed McMahon on the show, and how they always held it down with their polished old school sarcasm.
A point that may seem random: as someone who's always been a supporter and lover of hip-hop, I've always remembered The Tonight show as the landmark of a cultural crossroads: the last representatives of pre-Hip-Hop America. On the Tonight show in the 1980's Ed Mcmahon and Johnny Carson were the last men standing as gatekeepers of a world where hip-hop remained invisible. It's a testament both to hip-hop's power and to Ed McMahon's longevity that he was around to see things change so much since then..