Apple claims more than 25 million copies of QuickTime 6 were downloaded in less than 100 days.
The company feels the multimedia player's popularity translates into strong demand for the open standard MPEG-4 format on which QuickTime 6 is based.
Apple is keen to push itself forward as a leader in providing end-to-end MPEG-4 streaming solutions.
Popular Apple’s senior vice president of worldwide product marketing Philip Schiller said: "QuickTime 6 has taken off like a rocket, with over 25 million downloads in 100 days.
"Why pay for a proprietary streaming solution when Apple is offering the first widely distributed end-to-end, open-standards-based streaming solution for free?"
Apple also claims nearly 200,000 downloads of its free QuickTime Streaming Server and Darwin Streaming Server.
Jeff Dodes, vice president of new media for Jive Records, said: "Jive Records used MPEG-4 to deliver a massive number of video streams of Britney Spears’ on-line exclusive, ‘I Love Rock and Roll’.
"QuickTime 6 has allowed us to deliver incredible quality audio and video from one of our hottest artists to her fans around the world."
QuickTime 6 with support for MPEG-4 was released on July 15 and is Apple's standards-based software for developing, producing and delivering high-quality audio and video over IP, wireless and broadband networks.
QuickTime 6 is available as a free download to Macintosh and Windows users.