Despite the fact that every other console and its dog has it, I never expected any form of film playback to be launched on Nintendo's DS, it's just not that kind of console. Nevertheless Japanese types will be getting just that feature as of next year. DSVision, as it is to be called, works much like homebrew in that content is downloaded to a microSD card, inserted into a DS cartridge and then loaded on the console. IT won't be restricted to just films either, e-books, TV programs and comics will also be available to download for use on the device.
How the playback itself will work is unknown, so queue speculation as to what use of the dual screens will be made. My vote is on video up top (the better quality non-touch screen) and menus down below; this would also allow a better viewing angle with the DS on a table on, say, a train or plane. Annoyingly no info is given about codec support, so it may be that all files are in proprietary (DRM-ed) formats which could annoy some prospective owners.
Initially the card will only be available in Japan. A starter pack with a 512MB microSD card and the DS cartridge adaptor will set you back ¥4000 (around £20) if you happen to be in the Far East although as yet no information is available as to how much downloads will cost. No details are forthcoming as to a UK release date either, but it's probably safe to say next year at the earliest if at all.