The leaders are preparing deeply for the first TV debate. So I think an American should give a view of how the American debates operate. First all three debates are televised on every channel that will cover it. They pool into one video feed so no matter where you tune in you are watching the same thing. This enables three different debate formats. The first is usually a stand-up debate about domestic issues. The second is a sit-down about foreign and defense (defence) policy. The third is a town hall where the candidates are asked questions by 'real people' on a mish-mash of subjects. They are hyped by the media and can have defining moments. But for the most part they are incredibly dull and change the views of very few people. In the American system they are essential because the people of America go into the polling booth and choose between the two people on that stage. I personally believe in the British system with the short election span and the fact you vote for an individual MP and not the leader there only needs to be one debate. This first debate will be exciting and informing for the British people. The other two will be uninteresting and a waste of time.
P.S. I think Brown will do better than people think. Remember he is the only one who has had to answer tough questions weekly for nearly three years.