If you want more detail, there's this excellent dissection of the No campaign's offensive leaflet, and this incredibly helpful and straightforward explanation of AV.
I'm not a particular fan of how either side has conducted themselves during the run up to the referendum, but I did just want to highlight a couple of quotes from those heading up the No campaign:
David Cameron - "(AV) is obscure, it's unfair, it's expensive, it could mean that people who come third in elections will end up winning... I feel in my gut that AV is wrong"
I feel unqualified to comment on what Cameron's gut may or may not tell him (maybe Matt Baker knows more than me, thus prompting him to ask our PM how he slept at night), but it is fair to say that it is possible for a candidate to come third in the initial count and end up winning when all alternative votes have been counted. Possible, but very unlikely in practice. The claims that it is unfair and expensive are much easier to dismiss - AV is neither. If anyone tells you that it is, ask them to explain how and why. Despite having a bone to pick with him on a totally separate matter, I have to hand it to Johann Hari for his excellent recent article - if you get the X Factor, you get AV. And the Independent has published a clear, concise and compelling article to support its Yes to AV stance.
William Hague - "It would be unBritish to change to a system (AV) that is unclear and more expensive and would produce many problems"
14 pints a day Hague goes one up on his boss. It's not his (beer) gut that is against AV, but rather AV is against the very essence of being British. Oh please. And I love the fact that the "many problems" alluded to go undefined.
Baroness Warsi - "... there is an even bigger problem with AV: It gives more power to extremists. Why? The whole system is so complicated the problem is all too easily obscured"
So complicated in fact that The Sun requires a small box containing fewer than 80 words to explain it:
What is AV?
On May 5 the nation votes in local elections AND the referendum on AV.
Under our first-past-the-post system, the candidate with the most votes is elected. Under AV, voters rank candidates in order of preference.
If no candidate achieves 50 per cent or more of the vote, the one with the fewest votes is eliminated and their votes are redistributed according to second preferences.
This continues until one candidate achieves 50 per cent.
That really is honestly it. Fewer than 80 words to not only explain AV, but to also explain FPTP and remind us when to vote. All the obscurities, all the complications. The lot.
And why oh why, if AV gives more power to extremists, is the BNP urging its members to vote No to AV on Thursday 5 May?
Between now and the referendum, I urge you to visit both the No to AV website and the Yes to AV website.
Refresh your memory of the actual posters used by the No to AV campaign (and do have a play at making fake posters), and why not read what a fair dinkum, green and gold aussie has to say about it all - some absolutely fantastic blog posts from someone with experience of dozens of Australian elections using a system similar to AV, including debunking many of the myths peddled by the No campaign.
No, Australians aren't looking to dump their election system. No, Australia didn't have to introduce compulsory voting as a result of adopting their election system. If you only read one of Antony Green's blog posts, read this one.
And please do take the opportunity to vote on Thursday 5 May!
Goodnight grown up, honest political campaigning, wherever you are
P.S. A late honourable mention to the below:
P.P.S. Final word to the invariably excellent Sir Charlton of Brooker.