It was pretty good, basically a convention speech. Not excellent like Obama's or Palin's, but pretty good. He defined the differences between himself and Obama using the regular party rhetoric, pretty standard fare. In the early part the audience was very reactive, sometimes too reactive wrecking the flow of the speech, but he handled that pretty well.
Twice at the early part of the speech he was interrupted by a protester, but you couldn't hear the person and the crowd drowned them out with chants of "USA, USA!"
Even that didn't seem to phase him. As the speech went on he then went into some details of his plans and policies, at that time he seemed to be more comfortable, settle into the speech, and therefore did better. He began to get excited and to draw the crowd in, they really started getting into it.
I'd rate it a B+ as compared to Obama's A... And if you were comparing him to Bush, well, there is no comparison. He is far, far better than Bush at public speaking who at his absolute best gets a C.