Seems that countries selected were based on results at WOC12. The top 13 teams were invited plus the host country (Columbia). The remaining spots then went to the best team in each IOF region. Since NZ was better than Oz, NZ got the Oceania spot. Similarly, US outperformed CAN at WOC12, so US got invite for North America. Brazil for South America, RSA for Africa, etc.
Judging from previous results, competition seemed pretty high with names like Simone, Tero, Minna and Hubmann among the medalists.
http://en.wikipedia.org/wiki/Orienteering_at_the_W...