It seems the rumor was, well, nothing more than that:
It had previously been touted in fashion circles that the supermodel was set to launch a line of clothing and footwear, dubbed Bundchen by Dolce & Gabbana, this spring, with a blow-out party already being planned to celebrate its arrival.
Guess which fashion circles were doing all that touting? On December 20, 2007, British Vogue said the line would be called "Bündchen by Dolce & Gabbana" and launch "next spring." It even noted Dolce and Gabbana themselves "encouraged [Bündchen] to get in on the act with them."
Then on February 25 British Vogue reported a "star-studded party" was in the works to celebrate the launch of the collection, and it would be followed by parties in New York, London, Dublin, Paris, Barcelona, and São Paulo. The magazine even projected sales figures for the line of $200 million in its first year. That's a lot of parties that won't be happening and money that won't be made.
Where on the World Wide Web could all this have started? Many Websites, like British Glamour, British Marie Claire, FabSugar, and Catwalk Queen picked up on the story on December 20, at the same time that British Vogue did. However, on December 19, a "celebrity tabloid" called the Pop Crunch Show reported Bündchen would produce "a 'chic and feminine' springwear line, called 'Bündchen by Dolce & Gabbana,'" which would hit stores in 2008. If British Vogue found the story on Pop Crunch to begin with, where did it get all that other bogus information?