While Declan Kidney's men rise one place to sixth, the Pumas drop three places to ninth with Wales and Samoa rising one place.
Following the crucial result for Ireland at the Aviva Stadium, Gordon D'Arcy paid tribute to the contributions made by 19-point out-half Jonathan Sexton and the front row and second row.
"The tight five were superb. They're absolutely shattered," admitted the 71-times capped D'Arcy.
"I take my hat off to them. It's a very Irish thing not to tell people when they do stuff well, but I was the first one over to those guys.
"You might take Johnny for granted but we don't, we're absolutely blessed to have him. His selection of plays was first class and he showed why he's one of the best out-halves in the world. He controlled the game."
With the rankings, as they stand following the update on Monday, December 3, being used to determine how the 12 directly-qualified teams are banded for the 2015 Rugby World Cup pool allocation draw, the past weekend was the last chance for several teams to determine their seeding.
Teams placed one to four in the world rankings will comprise band number 1 and will be drawn randomly across the four World Cup pools, so will crucially avoid playing each other until the knockout stages.
The teams ranked five to eight will form band 2 and the remaining four directly-qualified teams are in band 3. The eight places available through the qualifying process will be split into bands four and five according to strength.
As the rankings stand at the moment, the bands for the 2015 Rugby World Cup draw would be:
Band 1: New Zealand, South Africa, Australia, France
Band 2: England, Ireland, Wales, Samoa
Band 3: Argentina, Italy, Tonga, Scotland
Victories for the top four sides in the world on Saturday guaranteed their band 1 seeding for the next week's draw in London.
New Zealand's place at the top of the rankings was never under threat, while narrow wins for South Africa, Australia and France consolidated their places in the elite quartet.
IRB WORLD RANKINGS (as of Monday, November 26):
Last week's positions in brackets -
1(1) NEW ZEALAND 92.91 rating points
2(2) SOUTH AFRICA 86.94
3(3) AUSTRALIA 86.31
4(4) FRANCE 85.07
5(5) ENGLAND 81.07
6(7) IRELAND 80.22
7(8) WALES 78.95
8(9) SAMOA 78.71
9(6) ARGENTINA 78.71
10(11) ITALY 76.24
11(12) TONGA 76.10
12(10) SCOTLAND 75.83