One of the most annoying aspects of our current electoral system is the issue of tactical voting. This is where voters feel compelled to vote for someone over their preferred candidate as otherwise someone they really don't want might sneak in thanks to the split vote. It's something that's sadly very common with the current First Past the Post system. You'll often hear politicians on election night discussing swings towards various candidates around various issues and it's all based on hearsay from the campaign trail. No one really knows why the voters voted for a particular person and there is much tea-leaf reading done by the psephologists in interpreting the results for a ward.
Political parties are not one size fits all stereotypes - all of the main parties have a fairly broad coalition of views. Knowing the preference voting order of the voters will give a much greater insight into the nature of the electorate which can only be a good thing. We will no longer assume that all Tory voters are Eurosceptic social conservatives or supporting the LibDems implies you are a Labour refugee or the Labour party draws all it support from militant union membership. And by raising the bar an MP has to reach they will have to broaden their base and not just rely on there being slightly more of one set of voters than the other platforms.
I have to say so far neither of the campaigning groups has particularly impressed me although the No to AV campaign do seem to be edging ahead in the negative campaigning. However the electoral commission does do a good neutral booklet that explains how AV works without any spin either way. It's worth a read.
While I hope I've done my bit to convince you of the benefits of voting yes (feel free to comment if you want debate!) I do urge everyone who has the right to actually turn up and make their views known. These decisions are only made by those who turn up and if turnout is low it will be a long time before your views on the electoral system are canvassed again.