The VG Chartz site claims that the Wii now controls 41.6 per cent of the market with 10.57 million consoles sold, while the Xbox 360 has been pushed into second place with 10.51 million sales or 41.4 per cent market share.
VG Chartz said that its monitoring system is more accurate than other services because it does not use manufacturer shipment figures and claims to estimate current console sales.
"VG Chartz collects data directly from retailers all over the world," said an official statement from the site.
"Retailer sample sizes are small compared to professional tracking services, but are large enough to provide very accurate projections of the latest console sell-through figures worldwide."
Nintendo's success was backed up by figures from independent UK sales tracking company Chart Track, which said that sales of the Wii in Britain have now surpassed one million.
That makes Nintendo's games console the fastest ever selling home console in UK videogame history.
"Wii has passed the one million sales figure in just 38 weeks, some 11 weeks faster than the PlayStation 2 and 22 weeks faster than the Xbox 360," said a statement from Nintendo.
Nintendo added that the sales figures give the Wii 68 per cent of the UK console market.
"The non-stop demand for Wii even in the traditionally slow sales periods for videogames in the UK is clearly behind this record breaking achievement," said David Yarnton, general manager at Nintendo UK.
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