I would actually be quite scared to bicycle in NZ. Especially in the rural areas. The roads are often narrow and winding without shoulders to speak of.

There's a steadily increasing network of multi-day off-road cycle trails being built. http://www.nzcycletrail.com/map/ (click on Map View).

I didn't know that. I'll have to check it out when I'm there next.

I live in Wellington and bike to work every morning (8km). Sure Wellington is not well set up for cycling - the streets are narrow, bike lanes are few (although my route is OK). However if you're not an arsehole on the road and keep an eye out for hazards, it's not too bad. NZ drivers in general have a very low opinion/respect/tolerance for cyclists, although Wellington drivers seem to be a lot more polite than elsewhere.

Auckland at least is making steady progress, depending on where your commute is. I cycle an hour each way to work, and there's only about 500m total where I have to join the car lanes. Rest of the way it's bus and cycle lanes.

Sure, but it is not like you couldn't get punched by some angry motorist in any country in the world. Except maybe Japan.

I've biked in several major American cities and nowhere have I ever heard of a cyclist getting tackled and punched by a motorist. I've gotten yelled at and had stuff thrown at me by angry motorists, but nothing like what Russ saw in NZ. At the time it happened, Russ blogged about it a bit and he also had never seen anything like it in all of his cycling miles in the states.