That's something I have been thinking as well, but I never posted. After all, Roberts WAS Rehnquist's clerk and I assume they got to know each other pretty well.
I learned that as recently as yesterday, and it makes alot of sense. Rehnquist would have had alot of confidence in Roberts, and may have even played a roll in getting the ball rolling on the initial announcement several weeks ago. I can remember alot of FReepers had no clue who Roberts was at the time. I know I didn't, beyond being one of the best litigators to enter the halls of the USSC.