Chris Dillow has a good go at the Government's "Thatcherism - Choose Your Own Adventure" Web site and the Have Your Say-style idiots who frequent it. But the fate of another, related Government Web project is interesting.
The number10.gov.uk e-petitions site will be remembered mostly for its role in kiboshing the horrible "road-pricing" (aka total surveillance of all vehicle movements) proposal. It's now officially "under review", and isn't accepting any more petitions or signatures on existing ones. (Also, the ones that were outstanding at the election have been binned.) At the same time, a variety of suggestions-box websites have proliferated across the public sector.
The distinction is clear; the e-petitions project was intended, among other things, as a way the public could protest about policies it didn't like. The example of road pricing shows that it was more effective in this role than cynics like me might have expected. "Spending Challenge" and friends, however, don't lead to anything - nobody has to respond to them, there's no mechanism to build a campaign on. It's just a pipe leading to the government's File Zero.
Also, the e-petitions site was engineered by competent people, notably Chris Lightfoot. The Coalition's multifarious efforts went online and duly crapped out as soon as production traffic hit them. You can read how MySociety scaled up the e-petitions system here. It's the Big Society for you - a meaningless suggestions box for half-literate blowhards, as opposed to a fairly useful tool, incompetently built by SomeCompany, as opposed to MySociety.