In reply to stone monkey:
Its a mixed bag.
Auckland: some degree of smog, rush hour traffic that makes Bangkok look not so bad, a somewhat dreary suburbia and a cityscape that is a little dull (relative to Europe). On the plus side it's a hell of a lot more striking and pleasant than the tube ride from Heathrow to central London
Wellington: only been there twice, but on a good day it is the best NZ has to offer. Much of the time it seems to be having a bad day weather-wise, in which case it'll resemble something akin to what we're about to go through this Monday. Windy as hell.
Christchurch: a lot of people rate it, but I have my doubts. Maybe because I'm used to the slightly more tropical and cosmopolitan nature of Auckland, Christchurch did nothing for me. But it is close to some outdoor pursuits. Windsurfing, surfing, skiing (water and snow) and gliding were all easily accessible for me, although Auckland has no climbing wall and climbing in general is largely either bouldering or alpine.
Nelson is becoming rated, but I suspect property prices are booming also.
Keep in mind, a lot of the distances are so large in NZ, that you are just as well off in the UK - fjords, mountains and the Med are probably just as accessible to a Londoner as the equivalent options are to a Kiwi in Auckland.
NZ isn't a bed of roses either. We have a surprising violent crime rate, a growing underclass and income inequality, and a population that has had it good for so long they have forgotten how lucky they are - and growing a bit narrow minded as a result. It has got all the crap you get over here, but just on a much smaller scale, and in general, in keeping with the size, everything is just a bit slower and a lot more personal. Expect good service, but also expect to work hard; the work ethic in NZ is demanding, and although you may do less overtime than here, time in the office is spent working, nothing else.