I've had a lot of trouble thinking about anything interesting to say about AV. On both sides the campaign has been unconvincing and, frankly, boring. The "No" camp has stuck to simple and predictable lines of attack such as: first past the post is "clear, simple and decisive," and AV is "undemocratic and... much more complicated than what we have." The "Yes" campaign was only marginally more interesting when it attempted to inflate the issue's importance with hyperbolic rhetoric: Nick Clegg accused the Tories of a vast, intergenerational right-wing conspiracy  while Chris Huhne made a hollow threat  to sue. How cute.
Despite the best efforts of the belligerents, I still struggle to care. The facts are these: the referendum will not end debate on electoral reform, since the twin bugaboos of proportional representation and reform of the House of Lords lurk still in the wings. Nor will the referendum, regardless of outcome, make our system "more democratic"-- not that this would be a good thing, since for seventy years "more democracy" inevitably meant more bureaucracy, unsustainable deficits and a lot of unwanted, oppressive and inflexible laws, with negative implications for day-to-day life. So why on earth are Libertarians talking about AV at all-- which seems, by comparison, such an inconsequential issue, a procedural tweak of a right we exercise for thirty seconds every five years?
Because libertarian ideas, despite the impressive arsenal of philosophy available, have failed to penetrate cosmopolitan consciousness. Libertarianism today is a victim of being born within a successful system that (i) was historically quite stable; (ii) had governments able to derive long-term legitimacy from welfare programmes; and (iii) was capable of guaranteeing security through military force.
Under these conditions, we have developed a broad, common, self-reinforcing, and very naff body of thought known as the conventional wisdom that, per J.K. Galbraith, "accommodates itself not to the world that it is meant to interpret, but to the audience's view of the world," its key feature being that "it has the approval of those to whom it is addressed," and at any rate a framework within which libertarianism, qua critical ideology, does not fit. This is because, Galbraith wrote, "There are many reasons why people like to hear articulated that which they approve. It serves the ego... (it) is a source of reassurance... (and) it means that others are also hearing and are thereby in the process of being persuaded," creating the basis from which misadventures like the AV referendum might be launched. Because of this conventional wisdom is difficult to overcome through the application of philosophy: "Ideas", he added, "are inherently conservative. They yield not to the attack of other ideas but... (only) to the massive onslaught of circumstance with which they cannot contend."
This conventional wisdom is, in this way, quite repressive; and this is part of the reason that libertarians should feel left out of the AV debate. Despite being given the illusion of a choice between "Pro AV" or "No AV," on reflection the libertarian discovers that the choice is an impossible one, since accepting the referendum as a legitimate discussion requires acceptance of the conventional wisdom, a welfare-state logic he traditionally rejects. As put by Marcuse, "Under the rule of a repressive whole, liberty can be made into a powerful instrument of domination"; the freedom to choose is rendered useless when outside forces dictate what may be chosen, and "Free election of masters does not abolish the masters or the slaves."
Libertarians seek to minimize the existence of masters generally, particularly the state, a goal which currently no major UK political party is prepared to adopt and we are, therefore, only notionally able to participate in mainstream policy debate; free elections of whatever major party will not change the fact that in Britain, the tax-to-GDP ratio hovers around 40%, the state gags private citizens  and the media over trivial information and singing Carl Douglas constitutes a hate crime . In this context, the central question for all reform of any kind -- electoral, fiscal, penal, or otherwise -- must be: will this reform emancipate individuals? And if not: what position can we adopt to try to steer public debate in our direction?
The answer is not to lose hope, to keep writing and keep moving; as put by Sam Bowman, to "'stand athwart history, shouting'... Faster!" For everywhere we look-- Greece, Spain, Japan, here in the UK, and even in the United States-- the onslaught of circumstance operates to prove libertarians right: global economic shifts, individual empowerment, demography and the structure of democracy itself conspire together to undermine the foundations of the western welfare state. As the catastrophe unfolds, the conventional wisdom will cling to the old ideas, the quartet will play the same familiar tunes-- "our institutions are sound," "our way of life is sustainable"-- despite a growing recognition from all quarters that Western governments will, one day this century, no longer wield the coercive and economic power to meet the obligations they set themselves in the last one.
In the meantime, however, I suggest getting used to being told you're wrong.