I have been waiting for this for a long time, and it really does work on Tiger. Unfortunately for me, many videos are now gone...
How it works: you basically enter the entire BBC web address of the video and wait for "download completed". It did not work for me a few times at the beginning, but then it started working very well (with the same videos), so I would advise anyone to try more than once. I have had some "script errors", but then it worked fine (sometimes I just wait for a day or so).
A few suggestive features:
1) Downloading in high quality?
2) Downloading multiple files at once or one at a time automatically
3) A status bar
4) In case no. 2 is not possible: once download is complete, rather than closing down, the application could ask if one wants to download another video (and/or "open file location")
5) Preference to choose download folder
I'm not a developer, so forgive me if what I am suggesting is not possible.
Thanks again a lot for making this available to Tiger!