For me, the most important thing about the Palin pick was what it signaled about the direction McCain wants to take his campaign thematically—a reformist “fighting for you message” focused on middle-class voters. Here’s the key passage:

Like the entire industrial Midwest, Dayton has contributed much to the prosperity and progress of America, and now, in these tough, changing times, after all you’ve done for our country, you want your government to understand what you’re going through, to stand on your side and fight for you. And that’s what I intend to do. That’s why I’m running for president: to fight for you, to make government stand on your side, not in your way…
…it’s with great pride and gratitude that I tell you I have found the right partner to help me stand up to those who value their privileges over their responsibilities, who put power over principle, and put their interests before your needs.
I found someone with an outstanding reputation for standing up to special interests and entrenched bureaucracies; someone who has fought against corruption and the failed policies of the past; someone who’s stopped government from wasting taxpayers’ money on things they don’t want or need and put it back to work for the people; someone with executive experience, who has shown great tenacity and skill in tackling tough problems, especially our dangerous dependence on foreign oil; someone who reached across the aisle and asked Republicans, Democrats and independents to serve in government; someone with strong principles of fighting spirit and deep compassion; someone who grew up in a decent, hardworking, middle-class family, whose father was an elementary school teacher and mother was the school secretary.

This is exactly where McCain should be. Now he needs a middle-class tax cut to make the package complete. Cesar Conda has a great piece making the case for it today. The bottom line:

Armed with a big middle-class tax cut, McCain would be better able to compete for the independent working- and middle-class voters in swing states like Michigan and Ohio who hold the keys to the White House.