History was made tonight as Britain held its first leaders' election debate. (Or more accurately, the first debate between the three biggest UK-wide parties.)

Gordon Brown, David Cameron and Nick Clegg got off to an uncertain start, with Clegg nervous as he opened the debate. But the Liberal Democrat leader must be delighted with his performance, as ITV News and YouGov both proclaimed him the winner.

That said, the BBC's Nick Robinson made a fair point: debates have no winners. We all watch with our own prejudices and values. Labour's Alan Johnson said Brown was the victor, while William Hague said Cameron came out on top. I think they're wrong, but who am I to say? The real test will be how the leaders came across to millions of voters, especially in marginal seats.

I didn't think Cameron was as bad as some have argued. But his curse is to be seen as the successor to Tony Blair. We're suspicious of slick politicians, after discovering from Blair that that smooth-speaking politicians are the last people to trust. And the Tories have been so muddled in their thinking (slash spending? cut taxes?) that no one knows what they'd do if Cameron moved into Downing Street after 6 May. (Lesson from the past: Thatcher doubled VAT in 1979 despite not breathing a word about this bombshell during that year's election campaign.) 

The debate reinforced the view of many of us that Britain's electoral system is fundamentally unfair. Some people's election votes carry far more weight than others, which is outrageous. We must never repeat the travesty of 1983, when the Liberals and SDP won almost the same proportion of the vote as Labour but got a fraction of the parliamentary seats. I hope that the three debates help nudge the British public to share their votes more evenly, to force a fairer voting system.

The other lesson, for me, was that social media made the debate far wider than the three men in suits, watched by a studio audience told not to cheer, applaud or boo. I loved seeing what people were saying on Twitter, and sharing my thoughts and weak jokes. It made up for the ridiculous, Orwellian rules constraining the debate. (Are the politicians really so frightened of the public that they need such protection?) We've got another three hours of debate before polling day. It should be surprisingly interesting.