Rehnquist's answer to the retirement question: "I am not about to announce my retirement. I will continue to perform my duties as chief justice as long as my health permits."
The reality is that his health does not permit him to continue now, at least in a capacity that the nation is entitled to expect from its top judicial officer. In fact, he recused himself in a substantial number of cases from the last term because of his health and a dramatic turnaround in that regard seems unlikely. It seems clear to me that Rehnquist is addicted to the power and prestige of the office, and he has decided to have his death certificate serve as his resignation notice.
(For cross-post at Centerfield and comments posted there, click here.)