Good form equates to improved standings. There's no special benefits out of cup form, such as doubling of points during the tournament, but there are clear spinoffs for teams playing well.
New Zealand's best ranked bowler is spin veteran Dan Vettori, who is sitting at ninth, a jump of five spots, in the ODI list, sandwiched between the seriously underperforming England swing bowler Jimmy Anderson and Pakistani left arm giant Mohammad Irfan.
Tim Southee, on the back of his splendid seven for 33 against England, is the leading wicket taker in the cup, with 13. That has enabled him to climb 10 places to 12th.
Trent Boult's 10 wickets thus far have him up to 24th, a rise of a whopping 23 spots. To anyone thinking Boult is strangely low on the rankings, remember he's relatively new to the ODI game.
Boult has played only 20 ODIs, and until last October, had only made eight appearances. Eighteen of his 28 wickets have come in his last eight games.
So the counter-argument is that he's actually making rapid strides. Vettori, by contrast, has played 290 games over 18 years.
South African legspinner Imran Tahir, who bamboozled hapless West Indian batsmen in Sydney last week, is up to a career-high fourth, as are Australian left armer Mitchell Starc and Irfan.
Curiously the list is led by two players not at the World Cup, spinners Saeed Ajmal and Sunil Narine.
The first cup-involved player is third-placed Dale Steyn, who has been relatively quiet.
However, on the basis that the big names stand tall on the important occasions, expect the steely-eye quick to have a serious impact at the sharp end of the tournament.
South African skipper AB de Villiers is, to no surprise, the No 1 ranked batsman, ahead of Kumar Sangakkara - the only player with two hundreds at the cup as of yesterday - and Hashim Amla in a high calibre trio.
De Villiers is two rating points short of becoming only the 11th player to break the 900-point barrier since the current rankings system was introduced.
New Zealand captain Brendon McCullum is the biggest mover on the batting list, up 10 spots to 18th, although teammate Kane Williamson remains the country's best at No 6. Ross Taylor, out of sorts in the cup, remains 11th.
Irish pair George Dockrell (28th) and Paul Stirling (34th) are the highest ranked associate country players for bowling and batting respectively.
However hats off to Sri Lanka's brilliant veteran Tillekaratne Dilshan. Not only is he up to No 5 on the batting chart, but he's overtaken Bangladesh's Shakib al Hasan to be the world's top ranked allrounder. Not bad going at 38.
New Zealand have moved ahead of England into fifth place on the team ODI rankings, one point behind Sri Lanka.
Australia still head the list, 13 points above New Zealand.
