Looking over polling report, I see a lot of data that I have missed, which point to the continued rehabilitation of the Republican brand, as the party becomes John McCain's party, rather than George Bush's party.  Consider:

NBC News: "Now I'm going to read you the names of several public figures and organizations, and I'd like you to rate your feelings toward each one as either very positive, somewhat positive, neutral, somewhat negative, or very negative. If you don't know the name, please just say so. The Republican Party."

The Republican party is still a net-negative, which is bad.  But it is the best showing in over two years of asking this question:

CNN/Opinion Research asks "Next, we'd like to get your overall opinion of some people in the news. As I read each name, please say if you have a favorable or unfavorable opinion of these people -- or if you have never heard of them. The Republican Party." 

As you can see, this is again the best net showing for the Republicans in two years, and only the second net positive showing in that time.

Finally, USA Today/Gallup asks a simple favorable/unfavorable question.  Here's the responses with the bigger picture:

Again, we see that the Republican brand is in better shape than at any point since 2005.

That's the good news.  The bad news is that the brand is in significantly worse shape than it was in 2004, while the Democratic brand is in better shape.  BUT, the point is that there is more evidence that the Republican Convention was a game-changer, helping the Republicans move beyond Bush.  And that is an unconditionally good thing.

UPDATE:  Over at Race42008, Kavon Nikrad notes a detail in the Gallup polling that I had missed:

The percentage of Americans identifying themselves as Republicans has increased from 26% immediately before last week’s Republican National Convention began to 30% immediately after it. That increase, combined with a slight 2-point drop in Democratic identification from 37% to 35%, has reduced the Democrats’ formidable advantage in national party identification from 11 points to 5.

Republicans saw an even larger increase in “leaned” party identification, which is computed by adding the percentage of Americans who initially identify themselves as independents but then say they “lean” to a party to the percentage who identify with that party. Before the GOP convention, 39% of Americans said they identified with or leaned to the Republican Party, but that number has increased to 47%. Forty-eight percent now identify with or lean to the Democratic Party, down from 53% prior to the GOP convention.