http://news.bbc.co.uk/1/hi/entertainment/4870150.stm
BBC News (Sunday) - GNARLS BARKLEY MAKES HISTORYFrom BBC News today (sunday)
Crazy by Gnarls Barkley has made pop history as the UK's first number one song based on download sales alone.
Until this month, download sales could only count towards a chart position if the song could also be bought in shops.
But under new rules, downloads can be counted as long as physical copies go on sale the following week.
The song, used in ads for Zane Lowe's Radio 1 show, has been downloaded more than 31,000 times on all internet sites, a spokesman for HMV said.
Come of age
The song, which is not available in shops until Monday, knocked last week's top track So Sick, by Ne-Yo, off the top spot.
Gennaro Castaldo, spokesman for retailer HMV, said: "This not only represents a watershed in how the charts are compiled, but shows that legal downloads have come of age."
He said if physical copies fly off the shelves at the same rate it could vie for a place as the year's biggest seller.
"It is an outstanding single so I don't think we are going to see this happening with a song every week," he added.
"It probably will be one of the summer's hits."
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