That's interesting - I would say that Christchurch is very much missable! Perhaps I know it too well (having spend 5 years of school and 4 years of university there) but to my eyes it's not the most interesting of towns, though it does have some lovely old architecture and there are interesting things and beautiful places close by. Not much nightlife or shopping either, though the restaurant and cafe scene is now quite respectable. I guess it's more the attitude of ChCh that I don't like - smugly conservative. Wellington is about the same size but infinitely more intersting and cosmopolitan, plus it is more beautifully situated, but tends to be missed out by tourists because it's not particularly close to any of the big attractions.

I'll post some thoughts on Australia when I have a moment to do it properly.