I'm warming back up to Bucannon, in large part because of the Revis and Browner signings.
If you're going to play 2 deep safeties, then you want someone with exceptional range, vision, ball skills and coverage ability. Jimmy Ward, Lamarcus Joyner and Hasean Clinton-Dix fit that mold. But if you're going to play mostly a single high safety (Cover 1 and Cover 3) then you want a SS who can play in the box, support the run, and cover an underneath zone. Guys like Bucannon and Calvin Pryor should exel in that role.
The biggest question I have with Bucannon is how teachable he is, and whether he can learn to play with more discipline. And I still think I prefer Antone Exum, who has more versatility to play either role, or outside CB. But my interest is on the rise.