Here's a good SEO tip about using wiki for SEO. In fact, I use this one myself.

Wikis contain vital information about specific topics. The idea behind a wiki is to have a repository of user editable encyclopedia (wikipedia). The good thing about Wikis is that everyone can edit it and thus content collaboration is easily done. The bad about wiki is that everyone can edit it and thus it is prone to wiki spamming.

The technique described in the article is about contributing to Wiki (not spamming a wiki). If your site is a travel site about New Zealand, then it would probably be beneficial for people who are visiting a wiki about new zealand.

The idea is to contribute to the wiki and get to be a good resource for visitors looking for such information.

Check out the article here