KEY POINTS:
The IRB are making a big noise about their rankings being used to determine the top 12 seedings when the draw for the next World Cup is made this December.
Once the November internationals are finished - and all the major nations have significant programmes - the IRB rankings as of December 1 will be converted to 2011 World Cup seedings.
The top four ranked teams will be placed in different pools where they will be joined by one team each ranked between five and eight and another ranked between nine and 12.
Historically, the IRB have used the final placings at the previous World Cup to determine the next tournament's seedings and the system has been widely criticised on the grounds form fluctuates wildly between World Cups.
The new system is an attempt to reflect form over a longer period and there could potentially be some movement in the rankings between now and December 1.
New Zealand are currently ranked No 1 and if they win all five of their tests, they will stay as number one.
The IRB give ranking points only to the winning side. Other than World Cup clashes, the ruling body doesn't take into account the calibre of the opponent and make more points available for a victory.
New Zealand and South Africa are far enough ahead in the current rankings to be sure that, as long as they don't lose more than one test, they will stay there.
The most likely area of volatility lies between rankings three to eight. Australia sit in third but could be budged as they have to play the All Blacks in Hong Kong and England at Twickenham.
Argentina in fourth spot are also vulnerable as they are only just ahead of England. While England were poor on their recent visit to New Zealand, they pose an entirely different threat in London.
Their record at Twickenham is infinitely superior to their away work and it is the kind of ground where younger, inexperienced visitors can easily be overawed.
England will also have Martin Johnson at the helm and could field their most dynamic and creative midfield pairing for many years in Danny Cipriani and Riki Flutey.
The English will be keen to jump into fourth spot so they can avoid being drawn in the same pool as New Zealand, South Africa or Australia (assuming the Wallabies can retain their ranking).
The rankings have put an extra little something into the November tests but All Black assistant coach Steve Hansen, who previously had charge of Wales, believes the home unions, France and Italy have never lacked motivation at this time of year.
"I don't think it [the rankings] will make too much difference," he said.
"The November tests for the UK teams and France have always been the biggest games outside the Six Nations. They fall at the start of their season ahead of the Six Nations.
"It is the June tests that they have seen as a bit of a burden, falling at the end of their season and we have not always seen them select their best sides."
The expectation is that the All Blacks will face the best sides Scotland, Ireland, Wales and England can call on.
Wales, like England, have an outside chance of bumping their ranking into the top four and Ireland have a point to prove after coming close to the All Blacks in their last three tests in New Zealand without finishing the job.
