I hear that there is still a condemned zone in the heart of Christchurch after their earthquake. How much impact does that have upon tourist-related activities? Does it make it difficult to get around the city?
Lonely Planet has some recent articles that might be relevant here:
As someone from Christchurch, this is my cue.
I spent six months back there over summer. Sure, things have changed. The CBD is mostly closed off - although that's slowly improving as buildings are demolished and removed.
However, life goes on. Businesses have relocated to other commercial zones. Schools share and build new blocks. Bars open up in the surburbs.
As a tourist, much of the appeal of Christchurch is the outdoors. Yes, the famous Christchurch Cathedral is coming down, and the Arts Center market is no long accessible. But the museum is. The Botanical Gardens are as beautiful as ever. Many pubs and bars are open, and while the number of motel/hostel/hotel rooms are fewer, so are the tourists - just book ahead. The International Antarctic Center is open (I went over the summer) and is incredible and eye opening. Orana Wildlife Park and Willowbank have the Kiwi bird for you to see the national icon. Rugby is happening again in Christchurch with an All Blacks test just last week against the Irish. The beaches are open and the golf courses are calling your name.
Outside of Christchurch there are also plenty of day trips - from Hanmer Springs thermal resort, to the small French town of Akaroa, to the mountains if you're planning on skiing at Mount Hutt or Porters Heights.
As far as getting around the city goes, the buses are running, taxis are certainly still going everywhere, and aside from the very center, and some of the harder-hit eastern suburbs, from a tourist point of view it's still very accessible.
If you have any follow-up questions, please feel free to ask.
Just to clarify something others have said, the museum isn't actually open at the moment; it was closed a couple of months ago for earthquake strengthening. They are hoping to reopen sometime soon. Other than that, what people have said is more or less accurate. The visitors I've shown around have found the Lonely Planet page someone mentioned above particularly useful and as long as you get a hire car it's all pretty accessible. The cordoned area is shrinking all the time and with maps etc it's not too hard to navigate the city. The best way to know where to avoid is to download the latest red zone map from the CERA website which clearly show what parts are now open.
I was there 6 months ago, but from what I have heard on the news not much changed yet, except that they started to demolish the buildings inside the city.
So the city center itself is closed, there is a fence around and you wont be able to get into the city center. The other areas near the city center are pretty depressing, a lot of abandoned businesses and buildings, rubble and weeds growing on the main roads because nobody goes there any more. The other problem was that had to walk for ~1h to find any place that served any food - you see a lot of big signs for Indian, Thai, fish & chips etc on the streets; but after closer inspection it turns out that most of those places went out of business after the quake. Either bring your own food if you don't stay in an all-inclusive hotel, or get something from a gas station until you have time to scout out some better place.
In short, I wouldn't place Christchurch on top of your must-see list right now. Most of the attractions you know from pictures or tourist guides are either destroyed or closed to the public for renovations; except for things outdoors as Mark pointed out.
I have not been in Christchurch since April 22nd 2010. however growing up in the surrounding area and with family still living there hopefully I can offer some help.
Christchurch art's centre being inaccessible means the Theatre is no longer operating, the Art Gallery is also closed, there are still some cultural activities on offer, as Mark mentioned the Museum is still open as is the Ferrymead Historic Park.
City Centre the Casino is open 24 hours over the weekend (Friday - Monday) and till 3am the rest of the week, this provides a 24 eating and drinking option in the CBD. To my knowledge there is only one club in the CBD open which is a gay club that is 'accommodating straights' (remember it's their house if you don't like that then don't go).
Christchurch has typically had a 'Car Culture', the bus network while wide reaching is not as regular as similar sized European city's so even before the earth quake I would have recommended hiring a car (not all the roads are in great shape but are passable with some exceptions in the eastern and north eastern suburbs).
Adding to Mark's list of things that are open:
Victoria Park the scene of Peter Jackson's Heavenly Creatures a true story based on the 1954 killing of Honora Parker. Also a good place for short walks in the hill side, mountain biking and picnics with a playground for children.
The best thing about the South Island is its love of adventure activities; Queenstown is well known for it extreme sports, and the surrounding area's has plenty to offer.
Kite sports around the Ferrymead and Sumner area; this is a good way to get into kite-surfing, kite-buggying and kite-skiing.
Paragliding - learn to paraglide or take a tandem ride above Taylor's Mistake. And go surfing afterwards.
Fishing at Lake Coleridge and surrounding lakes(5?) and rivers(3) only a couple of hours drive from Christchurch and accessible in a 2WD car in summer.
If you happen to be interested in fishing / hunting or 4x4 in the South Island let me know and I'll get you more details.
If you have any further questions about the state of various parts of Christchurch let me know; my father operates a taxi in his retirement and would be able to give very detailed advice on most aspects.
EDIT: The Speights Ale House is open on Bealey Ave; there are 'container bars' on the corner of Bealey and Papanui Road and one down Victoria Street as well. The Monday club on Moorhouse Ave down near Madras Street is also an option.