Sunshine wrote: It is just

If he's as smart as I think he is, it's not because he thinks that anyone smart enough agrees with him.  Intelligent people should realize that other intelligent people can hold differing opinions based on their belief systems.  But as president, I certainly wouldn't want to have to deal with unintelligent opinions.

I think this is a little more than a token gesture.  I think Obama genuinely wants the perspective that a varied cabinet will bring.  He's said in the news, he's reading a lot about Lincoln and FDR these days, and both of them did the same thing he's doing.