A new political landscape?

I've never read any of his four million psychology/child-raising books, but Steve Biddulph has written a very interesting article in today's SMH suggesting that climate change, peak oil and growing awareness of ecological crisis will shift the political landscape over the next two federal terms to a two-party contest between Labor and the Greens, with the Liberals reduced to a minor party. I think he is right to suggest that we will only hear more about climate change (if that is possible) and peak oil (easy to hear more than almost zero) in coming years, however, I wonder whether both major parties will continue to shift to the ecological 'left', bringing into the mainstream environmental policies once viewed as extreme. I suspect that there is enough poll-driven pragmatism in Australian politics to keep the major parties alive for some time to come.