More than 100,000 people attended the Dunedin matches, and with thousands of visitors in the city, some Dunedin businesses have reported a 300% increase in revenue since the start of the event.
Economic forecasters are saying the best might be yet to come for the city.
Rugby New Zealand chief executive Martin Snedden said the new stadium was "remarkable" and had proved itself on the world stage.
He was at the venue for its first cup match, England versus Argentina.
"The buzz in the stadium, the amount of noise that night, the support for both teams, was incredible," he said.
The people of Dunedin and "the south of the south really warmed to the stadium", which was evident from a boost in ticket sales after the first game.
The results for Dunedin have been mirrored nationally.
Nearly 1.1 million fans have streamed through the gates of Rugby World Cup stadiums for tournament matches so far.
The official attendance stands at 1.07 million since the tournament kicked off on September 9.
The final eight of 40 pool matches were completed over the weekend.
In Dunedin, the ringing of bar tills appeared to indicate a dramatic increase in business.
The Craic Irish Bar co-owner Claire Grenfell, The Terrace Bar manager Warren Halford and The Duke of Wellington bar owner Michael McCarrigan said their takings had tripled for the month of September compared to the corresponding month last year.
"We've never seen anything like this in our history," Mrs Grenfell said.
"Sunday was like a double St Patrick's Day."
Mr McCarrigan said The Duke of Wellington had also sold three times as much beer.
"We've never experienced this before, and we're not likely to see it again for a long time."
Mr Halford said many of the visiting team suppporters became repeat customers.
"Once they found a place to have a drink, they would go to the game and come back for more." While it had been a hectic month for the hospitality trade, Mr Halford said he would gladly do it again next month.
"I would do it again the next month after that too. The Rugby World Cup has been very good for business."
Some retailers have also noticed a significant increase in their revenue.
Champions of the World Sport NZ Ltd manager Matt Clifford said large quantities of Irish, Argentinian, English and Italian rugby jerseys had been sold on game days, and many articles of All Blacks souvenir clothing were sold on the days following.
He said the store's revenue had jumped more than 300% in September compared with last September.
But not everyone was so lucky. For those based outside the city centre, it was business as usual.
Kensington Tui Clubrooms owner Sue Mackay said there had been no change.
"We're a little disappointed. It would have been nice to get more people through, but we weren't banking on it.
"Most businesses in the [outer] city were in the same boat."
Otago Chamber of Commerce chief executive John Christie said there had been a substantial economic benefit for the city, but the big outcome would be what happens as a result of that.
"Will it make a substantial difference to the development of business in the city?
"I think it will."
He said the coverage of Dunedin on international television had provided invaluable marketing, and many World Cup visitors would return home and rave about the city.
This too would create economic opportunity for Dunedin in the form of future tourism, he said.
Mr Snedden added to the mood of optimism.
"... Dunedin and the new stadium is in a very good position to put a case for regular, good quality, All Black test matches." Overall, he believed the entire southern region had "done itself proud" during its part in the tournament.
Feedback from all visitors to the area had been "universally and unanimously positive".
Dunedin Venues Management Ltd chief executive David Davies also believed it was the people, in particular the volunteers, who had made the four games "fantastic".
"I'm rather proud of it."
