Whether or not you support Barack Obama (and I will admit here that I do), and whether or not you think that he said everything he needed to say in his speech, I think he's demonstrated a good principle in "How to Respond to a Political Attack."
Lots of Democrats have said for years of dealing with the right-wing slime machine that we should ignore it and take the higher road. Well, that brings to mind an Israeli general who said something like, "If we're ten percent better than the rest of the world, we'll be a light unto the nations. If we're twenty percent better than the rest of the world we'll all be dead." Al Gore, John Kerry, and many others like them have found out the hard way that you can't just ignore the mudballs that the right wing throws at you -- you have to respond, and strongly.
There are others who will pick up their own mudballs and throw them right back at their opponents. But once that gets started, we start to lose sight of just what it is that we support about the people on our side of the aisle. If we scream about the other side's cheating, and lawbreaking, and dirty tactics, we have to scream when our own side does it as well, or we're no better than Karl Rove or Sean Hannity or any of the right-wing whackadoos.
Barack Obama's approach with this speech seems to be, "This isn't a mudball they've thrown at me, it's a baseball -- and I'm gonna try to hit it out of the park." More like political jujitsu than counter-punching, although that's still a bad analogy. While I don't always agree with Jesse Jackson, he summed it up perfectly: Obama saw a chance to turn a problem into an opportunity, and may come out of this crisis stronger than before.
The real problem, of course, is that none of us here can make a fair judgement as to whether Obama's speech was a success or not. That question will soon be decided by the American people. (Not to mention the media, who will decide just how much of the speech many of the American people will actually see.)