Actually, after the first presidential debate in 1960, there was a hiatus of 16 years until the next debate in 1976. During this time three elections occurred.
When the debates did restart, they never achieved the popularity of that first occasion. The first US Presidential election debate 66 million viewers and that was from a total population of 179 million people.
The contestants candidates will no doubt have a host of body language experts and media guru's grooming them thoroughly. Their every move should act to indicate trustworthiness and approachability, good humor and utmost seriousness, intelligence and the common touch. That's even before they've opened their mouths! It's certainly a difficult balancing act.
You might be wondering if policy is all important at all. Drew Westen, an American professor of psychology, examined the way politicians communicate with their audiences and how we perceive their messages in his book, The Political Brain. His conclusions are many, but one key insight is that it is the emotional part of our brain, rather than the rational part that is key when politics is involved.
One of the most famous examples of this appeal to the rational that is cited by Westen occurred during the presidential debates of 2000. Al Gore made a detailed statement about the differences between Democrat/Republican policy. George W Bush's reply has now passed into political history: “Look, this is a man who has got great numbers, he talks about numbers. I'm beginning to think not only did he invent the Internet, but he invented the calculator. It's fuzzy math. It's the scaring, trying to scare people in the voting booth.” Gore may have been addressing the issue, but Bush's easy bonhomie by-passed the specifics and made a broad emotional appeal.
There's lots of advice for those taking part that's flying around the internet, but let's hope the candidates don't manage to short-circuit our brains with a sweet smile or sad sob story. There is some consolation for the British, the Americans have started calling for a Prime Minister's Question Time-style form of presidential interrogation