I think it depends on how much money you've got. Can you afford to travel overseas on a working holiday? You've got to think about how much you'll need to get there, and to live there, versus how much you'll get for working. Working holidays are a great idea and a great way to see the world, but I would argue that it's potentially more expensive than university, particularly if you qualify for the government's HELP scheme.
Working Holiday Canda http://www.whpcanada.org.au/introduction.shtml
was present at The Big Meet
earlier in the year, perhaps you might be able to contact them to find out more information about it. I'm sure there are some other working holiday programs in other countries. Just do a search, I'm sure there are plenty around.