As this is happening, Twenty20 matches - whether international or domestic - are filling grounds in England, New Zealand, West Indies, Australia, South Africa and Pakistan. Sell-outs in domestic matches were very rare until Twenty20 strutted into town. The last challenge comes in April, when domestic Twenty20 hits India and vast grounds like Kolkata's Eden Gardens will have to be filled. But no one is betting against it - big crowds and big money are forecast.

So how will the ICC strike a balance between Twenty20 internationals and ODIs? If sponsors and the public are as wild about the World Championship - due to last just nine days - as they have been about domestic tournaments and one-off internationals then serious questions will be raised about the future of the 50-over format. In a crowded international calendar, something may have to give.

The ICC's tours programme, which sets out the international calendar in six-year blocks, has placed a limit on Twenty20 internationals. Each side can host just three a year. "There are a number of reasons for the limit," says David Richardson, the ICC's cricket manager. "To prevent overkill and to protect the domestic Twenty20 competitions. We also acknowledge that players are playing a lot of cricket and we don't want their schedules overburdened."

Will the limit ever be lifted? "I'd be surprised if it is to any great extent," Richardson says. "Part of the success of Twenty20 cricket is making sure it can coexist with Test cricket and one-dayers. They're different products and attract different crowds so we want to make sure that all three formats are preserved.

"Very importantly, we also need to preserve the attraction of Twenty20s at domestic level, here it is a great source of revenue and a real growth area. If you have too many Twenty20 internationals then the attraction of going down to see your local state or county play the format will diminish."

Steve Elworthy, Cricket South Africa's commercial manager and the main man behind the staging of the Twenty20 World Championship, believes that the variety of supporters Twenty20 attracts will boost the format's growth internationally. "Crowds tend to be a lot younger which hooks people into the game," he says. "You can watch a full match in three hours, go home or still go out afterwards. It's a different target audience to one-dayers and that's helping it grow very rapidly.

"We're expecting the South Africa matches to be very well supported and there to be a lot of overseas support at the Championship. It's always a challenge to fill a ground in South Africa when South Africa aren't playing, but I'm confident that Twenty20 is the best format out of the three to do this."

The ICC admits that the growth potential for Twenty20 is huge; cue a very happy commercial team. Although the novelty of relentless six-hitting can wear off, it's less of a problem when games can be wrapped up in three hours. Its shortness also means TV viewers are less likely to wander off - good news for advertisers. "Although there is less opportunity for TV companies to sell advertising time," says Richardson, "the fact that marketing guys can sell the format to different sponsors than one-dayers is a real bonus. Although you'll be selling less TV advertising than during ODIs, it will be more expensive."

With the ICC pumping millions into spreading the game globally, the crowd-drawing and moneymaking appeal of Twenty20s could also be enormously beneficial to the emerging nations. Scotland qualified with Kenya for the World Championship by getting to the final of the 50-over World Cricket League in February, but Roddy Smith, Cricket Scotland's chief executive, advocates a separate 20-over qualifying tournament and more Twenty20s for non-Test sides.

"Commercially, Twenty20 is more of a saleable event and you do get the crowds coming in. It would be great if there were more games between Test sides and the smaller nations and I think we will have more TV viewers in Scotland for the Twenty20 Championship than the World Cup."

Although the ICC hasn't considered a qualifying tournament for the World Championship, Richardson believes it will come if the emerging sides - made up mostly of semi-professionals - have time for it.

With the commercial benefits of Twenty20 clear at all levels of the game, Richardson doesn't rule out the possibility of it becoming the dominant one-day attraction. "It's a possibility," he says, "but it's a bit too early to say. Relatively speaking, the 50-over game is still very well supported around the world so we don't want to cannibalise it. I think the connoisseurs will tell you that Test cricket is the main attraction, then 50-overs and then Twenty20. We're very conscious of preserving the traditional forms of the game."

yes, 20-20 will definitely bring doomsday to 50 over one day matches. this apart it will bring in more european teams employing power as a way of playing cricket. i feel power will take over from technique as a transition from test matches to 20-20 games. i also feel that gradually india will get behind like as it happened in hockey with power play dominating these days, which is a weakness of india compared to the strongly built europeans. so called minnow teams now like netherlands will emerge as a strong contenders in future 20-20 world championships. and even 20-20 championships will open up new teams not traditionally cricketing nations coming to join party, countries like germany, russia, usa, spain etc and may even interest countries like china, japan, korea in the far east. Cricket then will be truly a global game reaching its best patronisation. as a true cricket lover, i will miss the beauty in test cricket. but at the same time i feel test cricket will become more beautiful thanks to 20-20 in as much as how the australians quick rate of scoring @4runs per over has started enforcing results in test matches compared to hitherto dull and drawing matches. Off late research has been done by teams to hit effortless sixes, hitting it as a projectile 45degrees up for best results and now being implemented in this world cup. similar several new things we will see in future courtesy 20-20 cricket. but its true that 50 over matches have become boring and i would love to get into watching 20-20 cricket even if it brings some perils with it. after all we all do evolve as time passes on, don't we?

i think surely 20-20 will cut the life span of 50 over cricket. There will be no chance for bowlers only batsman get the advantage. But 50 over cricket is really better and spirited game than 20-20. 50 over cricket shows the skill of batsman to play long inngs and bowlers also has a chance to show his skill. So my request is that the ICC should took a bold decission about the number of 20-20 games a country should play in a calander year. I think it is the only solution to make both games still alive.