And no, it's not because he is charming. He is charming, but this particular speech is notable because it highlights virtually positive quality that defines Obama - and should define the presidency.
Note not only the ease in which Obama addresses what could be devastating criticism, but how he does it. First off, he - willfully and eagerly - zooms in on Hillary Clinton's vice presidential offer, defiantly rejecting it. And he does so without making personal attacks, even finding time to praise her tenacity. Then he completely tears apart Hillary's stance that he isn't ready to be in charge - by citing Bill Clinton's stated desire for a VP to be ready to lead "in the first week." And he did it an admirably quick way that suggests excessive scripting wasn't the force behind it.
What makes Barack Obama worthy of the presidency isn't his gift for oratory. It's his calm, unflappable attitude in even the most difficult situations, coupled with a smart defiance and willingness to hit the sore spots upfront - all the while respecting his opposition on a personal level. Yes, he'd make a great vice president. But he'd be even better answering that phone at 3 a.m. In Columbus, he showed us all why.
Are we clear?