Both will be taking on Apple's iTunes Store in the American video download market. The Amazon Unbox on TiVo service is the first to combine downloadable video and traditional TV in one box. It is an extension of Amazon Unbox , the online retailer's digital download service, launched in the US in September 2006.
TiVo's 1.5 million US subscribers will be able to download content from Amazon.com's Unbox video download service directly to their set-top boxes.
Apple's newly launched Apple TV set-top box competes with the venture from Amazon and TiVo. The Apple TV uses content downloaded from iTunes.
Similar services on the way?
"I suspect we will see a parade of similar kinds of devices over the next several years," said Larry Gerbrandt, general manager of Nielsen Analytics .
However, Amazon's UK press office said it knew of no plans regarding similar services in the UK.
Amazon's service is linked up with Lionsgate , Paramount Pictures , Universal Studios , and Warner Bros film studios, as well as TV networks CBS and Fox . The trial begins today, when an unspecified number of TiVo subscribers will be able to test the service. The full service is likely to be launched "later this year", Amazon and TiVo said.
Films and TV programmes will be available to rent or buy, Bill Carr, Amazon.com's vice president of digital media, said. The cost will be $2 (£1) per TV episode, and between $10 and $15 (about £5 and £7.60) for most movie downloads. Movie rentals will start at $2. There will be no subscription fees for the Amazon Unbox on TiVo service.
WalMart's beta service
Twenty four hours earlier, supermarket giant WalMart announced that it has launched a beta version of a new Video Downloads Store where its customers can buy and download movies.
WalMart's new video download service will feature titles from all the major film studios - Disney , Lionsgate, MGM , Paramount, Sony Pictures , Universal, and Warner Bros - which is certain to annoy Apple. Some 3,000 films and TV programmes from Fox are already available on WalMart's download service, the company said in a statement .
WalMart is the single largest seller of films on DVD in the US, and has long prevented Apple from signing up with many Hollywood film studios due to its contacts there. Apple has so far only been able to offer films from Disney plus a few titles from Universal on its iTunes Store.
Films will cost between around $30 and $20 (about £15 and £10), and will be available to download on the same date they are released on DVD. TV shows cost around $2 per episode.
WalMart's movie service is only available in Windows Media, so the movies are not playable on Apple Macs or the Apple iPod .