If New Zealand is able to capitalise on their hosting of RWC 2011 to attract more events, as well as developing its reputation as a destination for sports tourism, combined with continued development of domestic involvement in sport related activities, the longer term impacts could be:
Consumer expenditure in the New Zealand sport economy by the end of the decade:
US$1 billion (NZ$1.2 billion)
Sport-related economic activity in the New Zealand sport economy by the end of the decade:
US$11.7 billion (NZ$14 billion)
Number of people working in sport-related occupations in New Zealand by the end of the decade:
Between 52,000 and 58,00
The big numbers have been getting a fair bit of press. Note that they're aggregated over a decade with no hint about whether any kind of time discounting's been used. Maybe that's the expected horizon of effects, or maybe it's just a convenient period for getting a big number. And never mind that "economic activity" doesn't have any particular connection with benefits: you have to net costs from measures of international visitor spending to get the activity's benefits.
They say international visitors, net of substitution and time switching, will provide consumer spending of $411 million that would not otherwise have taken place. But again, that's not net of the cost of providing services. And, if it includes visitor spending on tickets, the only way it counts as a benefit is by defraying the costs of hosting the thing; in the absence of the RWC, that portion of spending would disappear but so too would a not unreasonable quantum of cost.