The only reason that this has been driven up to the top of HN is because of its title. If it had been titled "A Nicely Designed Government Site", it would have gone nowhere.
As for the site, I can't see how the navigation would have me pulling out any fewer hairs than any other government site, but it is very large, multicolored and slidey, so if I were putting together an iPad commercial I might use it in a couple of shots.
I'm sure it all depends on what info you're after. But the site here have the typical info that people are after regarding the gouvernment on the front page. Most of the links there are related to the reasons we have government at all.
That's not how most government sites are structured in my experience, though I'm not from the UK.
As for the site, I can't see how the navigation would have me pulling out any fewer hairs than any other government site, but it is very large, multicolored and slidey, so if I were putting together an iPad commercial I might use it in a couple of shots.