What I took out of the puff piece (it's really a book advertisement, which if you need a quick heuristic, features a herd of sheep on its cover - something I instantly view as at best landing it in "pop science / economics / sociology done badly") is that they offered an incentive to game the system. The author is attempting to make a 'free market' tragedy of the commons argument to suggest that voters should be given incentives to vote.
The problem is two fold:
#1 Voters already have these incentives, but are informed by others (who certainly don't have altruistic goals) that these do not exist[1]
#2 Democracy, in America (arguably everywhere), is already driven by this mechanism, just not at the level that the author is addressing. It is called Lobbying. To use a quick metaphor, you pay to set the questions people get to vote on - this shouldn't be news to anyone with a moderate or above political understanding.
As for the WMD claims, beyond the simplistic level of common media, the question of Iraq's ownership of chemical weapons was never in doubt (the USA, France and so on sold them to Saddam / provided the engineering expertise to build them), it was whether or not Saddam was a) building more, b) reducing stockpiles and c) willing to use them ever again. Hans Blix was on record[2] as stating that Saddam was obviously not attempting a and c, and was attempting b[2].Thus, again, the people setting the question didn't like this conclusion, so re-framed the question as widely as possible to be proven correct.
A much more interesting question over all of this is how to separate beliefs from politics, or at the very least maximize the scientific basis for informed participation in society.
And that's not going to be solved by a book with a picture of sheep on the cover.
[1]It's called "living in a society", fire, police, health services etc which I realize will not be popular with a Libertarian readership. [2]http://www.telegraph.co.uk/news/worldnews/middleeast/iraq/70... - this is a right-wing source