Amazon is now offering digital videos by download onto TiVo Digital Video Recorders (DVRs). Amazon keeps a record of what was bought and allows the user to download it again (if they erase their hard disk).
The interface for PCs is much the same as for books on Amazon. I am not sure what it looks like on a TiVo. Also I am not sure how well this will sell. Amazon has had digital video download sales and rentals for PCs for some time. I haven't exactly noticed a lot of rentals or sales in my Amazon Associate store.
It will be interesting to see what effect video downloads has on Australia's limited broadband.