Greg Jaffe of the Washington Post has a good profile of Secretary of Defense Leon Panetta. I agree that Panetta is different, and less impressive, than his predecessor, Bob Gates, who was probably the best -- most effective -- SecDef in history. But Panetta's shortcomings, according to the article, have been more errors of omission than commission: he hasn't done enough to change things.
Jaffe makes one particularly insightful point: "Panetta sometimes sounds more like a congressman representing the
“Pentagon district” than the leader of the world’s largest military." Every SecDef has to be an advocate for his institution with the rest of the government, and Panetta seems to do that well. But he also has to be part of the national security team, and the evidence is that he has done that well, too. So the bottom line has to be that Panetta so far is well above average for the job.