Thanks for the welcome, phranque!
Really appreciate your response to my post. To possibly help you further clarify the best option (re the URL structure), let me give you a little more background to the website in question:
It is the online arm of a nationwide chain of jewelry stores in New zealand (and soon to be in Australia).
New Zealand has a very large (and ever-growing) Chinese community of which a significant percentage have demonstrated a liking for the widgets offered on this site.
So, in answer to one of the comments you made: "Yes, the local NZ-domiciled Chinese community is the target of the Chinese version".
Incidentally, what is the language code for Mandarin? (if you happen to know it).
Now, as far as the ideal URL format is concerned, on the basis of what I have just shared with you, would you still suggest a subdomain structure for each site as follows:
1) www.example.co.nz (for the English version)
and...
2) CN.www.example.co.nz (for the cantonese version)
Just asking (mainly out of naivety on my part), if zh-yue is the language code for a Cantonese targeted at Cantonese living in New Zealand, wouldn't the better URL structure be:
zh-yue.www.example.co.nz
Or would CN.www.example.co.nz still work just fine? Thinking from an SEO perspective as well as everything else.
The more I type these URLs in here the more I realize that up until recently, I have always associated subdomains WITHOUT the "www" for some reason e.g. CN.example.co.nz Until the web designer (that works on behalf of this client) actually talked about a subdomain WITH the www included, I didn't even know you could do that!
In closing, once again phranque, thanks for your wisdom and advice... and if you can clarify this further (based on what I have just posted here) that would be awesome and much appreciated :)
[edited by: bill at 4:50 am (utc) on Feb 11, 2015]
[edit reason] use example.com [/edit]