Some of the most recent ads to attack Barack Obama focus on age and experience. They use old clips from both of the Clintons and others to help make this point.
My own take on the "age" question has always been this: most people who are bad at making decisions continue to make bad decisions even as they get older. But rather than spend time citing evidence of Obama's tendency to make good decisions (of which there is plenty) I'd like to offer this very brief overview on presidential age. Obama would take office when he is about 47.5 years old which is only about 7 years less than average. Here are the Presidents that were younger than Obama (alternatively, they had less life experience):
Theodore Roosevelt, 42
John Kennedy, 43
Bill Clinton, 46
Ulysses S. Grant, 46
That's pretty good company on the whole. On the other end of the spectrum is Ronald Reagan who was elected at 69. Most experts agree he was showing signs of Altzheimers while still in office. Outside of Reagan, there have only been 4 other Presidents who took office within TEN years of McCain's current age (72 tomorrow):
William Henry Harrison, 68
Zachary Taylor, 64
James Buchanan, 65
George HW Bush, 64
Quite a distinguished crew there. Two who died not long into office and another routinely on the list of worst presidents. Somewhere in here is the makings of a good response to the age charge.