I've had very little to say on the subject of Arne Duncan, because I don't know a whole lot about him. A lot of people whom I label "reformers," and am therefore suspicious of (1), but who are also a whole lot smarter and more informed than I am, are cautiously optimistic about him. I look forward to changes to NCLB--better funding for failing schools, testing that makes sense and examines things other than a student's ability to fill in bubbles, things like that.
(1) I don't mistrust reforms. I mistrust reformers. As I was learning about how the educational world works, "reformer" meant "someone trying to destroy public education in favor of thinly-veiled parochial schools. I'm trying to change my views of both Arne Duncan and charter schools(2).
(2) although I still think that anything a charter school can do, a public school can (or at least should be able to) do better, more thoroughly, and with greater accountability.