According to the Chicago Sun-Times: 
Robert Novak has announced his immediate retirement following the diagnosis of a brain tumor, a prognosis the Sun-Times’ political columnist describes as “dire.”
“The details are being worked out with the doctors this week, but the tentative plan is for radiation and chemotherapy,” Novak said.
Not exactly the way I’d want to retire. Again, I say, Godspeed, Bob.
Link via Joyner at OTB, who says :
Roland Evans, whose name still graced the column until the end, died more than seven years ago. This day was inevitable, I suppose, given the human condition. Still, it’s the end of an era
That it is. I must say from a purely selfish perspective, I find it annoying, the timing of this thing, in that his insights would have been useful in this election season.