For all of my voting life, my vote has counted for very little. As a up an coming socialist at the age of 18, I distributed leaflets for the Labour Party in Egham Hythe. A solidly Tory area, my efforts were pretty much pointless. The first passed the post system meant my views were irrelevant. When I moved to Bradford, sure, my early voting for labour was always a winner. I kinda felt sorry for the others.
Then it happened. The Labour Party swung further and further to the right. My branch was suspended for opposing the first gulf war, and I decided to leave the party behind. When I voted instead for parties that had policies I agreed with (at first the Communists, then the Greens) the reality of the 'democratic process' was clear. As long as a party only needed to get past the next candidate, they could then do what they wished. they didn't have to compromise or build sensible alliances. They didn't have to listen to up to 60% of their constituency.
AV is not the system most would have opted for, and it will do little to change the chances of smaller, more progressive parties, (though thankfully the same can be said for the far right) but it is a move in the right direction. For that reason, any sane person should be voting 'yes' in tomorrows election. A 'no' vote is a vote for the status quo, a system that has led to terrible corruption and complacency by our political elite. Lets shake them up a bit.