In 2000, people thought Bush had surrounded himself with intelligent people, it turned out, his VP and cabinet, opened the door for the infiltration of lobbyists and massive corruption.
As Obama and McCain settle on their choice, I hope they choose a VP and cabinet without lobbyist or military ties (for my peace of mind!) Fortunately, with Obama, I don't think we have much to worry about. However, we should be careful to not pressure him into a 'bad' choice.
For instance, we shouldn't pressure Obama into adding well-meaning business leaders, like Buffett, into his cabinet, because no matter how sensible they are, they are in effect, going to be lobbyists for their business' interests. If McCain were to choose Romney as VP and win, this lobbyist proximity to the White House could be a problem (like Bush Sr and Cheney in W's admin).
Clinton, despite her passion for health care, would bring a lot of lobbyists with her if Obama asked her to administer a health care revolution.
Just some thoughts...