Although not entirely unexpected, this is still pretty devastating news--the reports of Dio's positive response to chemo were a manifestation of optimism. The news that the Heaven And Hell tour was cancelled should have prepared us for this.
I'm too shook up to really comment on this at the moment, except to say that of course there will be a tribute on next weekend's show.
For now I'd just like to thank Ronnie for the music and offer my sincerest condolences to his friends and family.
Ronnie James Dio, Metal Legend, Dead at 67 | Billboard.com