Kiwi captain Nathan Cayless shows the World Cup trophy to the fans
Winning the World Cup is about playing well for 80 minutes in the final.
On the day, New Zealand were better than Australia and thoroughly deserved their victory, thanks to an impressive team ethic.
To be behind by 10 points early on and to then claw their way back into the game and be dominant as they were in the second half was impressive.
I think most people were expecting the Aussies to run away with the game after the break and maybe for the Kiwis to capitulate towards the end, but it was the reverse.
As the game reached its climax, the Aussies came up with some unforced errors and the Kiwis played much better as a team and they deserved to be crowned world champions, even if very few people gave them a hope of winning going into the game.
Before the game, we were talking about the Australian superstars like Billy Slater and Darren Lockyer but I think today proved that if you perform well as a team you can beat a team that is full of individual stars.
Since losing to Great Britain 3-0 last year, the Kiwis have worked hard to turn things around, especially over the last six weeks.
The change of coach has certainly paid dividends and Stephen Kearney deserves a lot of credit for this win. His stock in coaching terms will rise ten-fold because of this while Wayne Bennett's influence has also proved important.
Coming into the final, we had expressed some concerns about the preparations of the two teams.
Australia have had easy wins over Fiji and Papua New Guinea whereas the Kiwis had to come from behind to beat England in Newcastle. They then had to win again last week in a high-pressure game and that put them in good stead for the final and gave them the self-belief they needed.
I thought their captain Nathan Cayless led magnificently from the front. He has been around the international scene for many years and played in the Kiwis defeat to Australia in the last World Cup final in 2000.
He led from the front superbly while Nathan Fien's kicking game was also crucial and Lance Hohaia injected some pace at key times
But for me, one of the biggest plays of the game, and the tournament as a whole, was Jeremy Smith's ankle tap to stop Johnathan Thurston with less than 10 minutes to go.
At that point, New Zealand were leading by eight points and Thurston had made a break through the line and looked odds-on to score.
Kiwi forward David Fa'alogo celebrates his side's victory in Brisbane
But Smith did enough to stop Thurston in his tracks and that effectively won the Kiwis the game.
There was a certain amount of controversy with the video referee decisions and although I have a slight issue with Benji Marshall's knock-on which led to Jerome Ropati's try, I have no problem with the penalty try.
Joel Monaghan had the option not to take out Lance Hohaia and if he didn't take him out and let Hohaia challenge for the ball, then it would have been a 50-50 challenge between him and Billy Slater and who knows what would have happened in that case?
But Monaghan decided to purposely take Hohaia out. It was a poor decision on his part and he suffered the consequences with the penalty try and ultimately the loss of the game.
Overall, this win is great for the game. There are some talented youngsters in the Kiwi squad, and although it is difficult for an Australian to say, there are lots of positives to take.
The tournament as a whole has been a great success and we have seen the emergence of some great players from emerging nations and in the final seen the red-hot favourites beaten by their cross-Tasman rivals.
The Kiwis have worked extremely hard and they deserve to have a couple of beers tonight.
Justin Morgan was talking to BBC Sport's Elizabeth Hudson