I know I'm a little late to the party, but I wanted to wait a little to fully absorb the content of Obama's speech so that I could write something other than "it was t3h AWESOME!"
This speech was certainly different from ones he has given before-- actually, it seemed like an amalgamation of his previous speeches. I liked the fact that he came off as a wonk during a segment of the speech-- a side he rarely gets to show when speaking to that large of an audience. He was most successful, I think, in being able to portray himself as being in touch with the everyday life of the American people. This is crucial because he was able to substantively make the case that John McCain is fundamentally out of touch. As Obama put it-- McCain simply "doesn't know." Brilliant.
It was, however, a bit too long. I watched this speech with a friend who deeply understands the importance of this election and supports Obama. He began to get a bit fidgety as the speech was well in to 25 minutes, but he was drawn back in towards the last 10 minutes or so. The phrases that stuck with him the most was when Obama proclaimed that the Republicans need to own up to their failures of the last eight years, as well as the line about McCain willing to go to the gates of hell to find bin Laden, but not the cave in which he lives.
I personally think Obama could fight back against the McRove slime machine by continuing to make the case that McCain wants to win such an important election by making it about the smallest of matters. It'll work: people will begin to see that this honorable man in John McCain is stooping to such dishorable tactics.
Oh, and of course, the speech was t3h aw3som3.