In Australian and New Zealand English, there seems to be a lot of ‘-ize’ (e.g. organize) spelling creeping into Aussie English.
Some people now seem to think it is okay to use ‘-ize’ selectively for words such as organization that are used a lot.
I agree, ‘-ize’ is being used quite a bit, which I think is partly because Microsoft Word so often defaults to US spelling. But I think we should use ‘-ise’ consistently because it is the more common Australian and New Zealand usage.
There is an interesting article on this topic at http://www.worldwidewords.org/qa/qa-ise1.htm
PS Some Australian writers choose to use ‘-ize’ if they are writing for a scientific or international audience.
