Australia, New Zealand & the South Pacific - Camping in NZ last week of December?

So, kinda tinkering around with possible destinations for my annual Dec 26-Jan 2nd vacation. While wandering around the Pacific Northwest today, the idea of a week-long camping trip in NZ might be quite neat. I'd probably want to stay in the realm of car camping - simply for the sake of minimizing gear to bring down. But I'd be up for a 1 or 2 night hike if nessessary. Overall I'd like to see as much as possible.

Any thoughts - is this a good time of year, or should I just turn my thoughts back to warm beaches somewhere else in the world?

It's a great time of year for camping, except for the fact that it's the Christmas / New Year holidays so campgrounds will be at their busiest. Still, this is NZ we're talking about so it's all relative. The most crowded places will be the traditional new year spots like Bay of Islands, Whangamata, Mt Maunganui, Kaiteriteri, Wanaka etc, and since I doubt you're coming to NZ to be surrounded by drunken adolescents you might want to choose your sites with that in mind. NZ has many fantastic places to camp - go for it!