I'm going out on a limb here, but I think I am probably correct. If Hillary Clinton had won the election and made the same cabinet choices as Obama, this would cause the Left to experience a collective head explosion. Although Obama's choices have raised the eyebrows of progressives, they have not caused a complete meltdown. And many mainstream media outlets have in fact praised Obama for placing "pragmatism" over "ideology" -- as if the two concepts are mutually exclusive.
During the Democratic primaries, however, progressives and the media engaged in very passionate, sometimes distorted, efforts to distinguish the two leading candidates on grounds of ideology. Many of them reserved the harshest criticism for Clinton's relationship with personnel from her husband's administration. They also viewed Clinton as most unacceptable on matters related to foreign policy. But now, Obama has not only picked many of the same people who received leftist criticism to serve in his administration, but he has chosen Clinton to formulate and implement foreign policy. If "hawkish" President Clinton had decided to keep Republican Gates at the Department of Defense, the progressive outcry would be deafening. But now, Gates is praised as a "Scowcroft Republican." That sounds like the Bush Doctrine: contrived and amorphous.
Perhaps the biggest thing Obama has done so far is make the Left reconsider its (or "our") vitriolic opposition to some of the Clintons' centrist/right-leaning political compromises. Or maybe Obama simply benefits from not being a Clinton. But progressives would never do something as irrational and discriminatory as describing the political decisions of one person as dangerous to the country while characterizing these same choices as smart, pragmatic or at least acceptable when another person makes them.