Using the footage you develop for a lesson, you can easily (and rapidly) develop a short video podcast to leverage your video footage. I would encourage you to add a running text line in your podcasts that highlight key points.
Actual eLearning use of this always uses 640 by 480 pixel video where complete text is clearly legible for users. This helps address ADA 508 compliance and also gives the very real option of use in settings that do not have audio capabilities.
The original file is 20MB and a bit higher quality than displayed here. This was entirely done with Windows MovieMaker (iMovie would work too). The version displayed in the session on the Blackberry was simply converted with Blackberry software. Super C is a free tool that can be used to convert to MP4 and many other formats with good results.
edit – Jan. 19, ’09: blip.tv post updated to reflect closer to intended 320×240 portable size. Also re-recorded with Blue Snowball mike and text included. License changed to Creative Commons. lol, why do Quicktimes always turn the bright whites into a dingy gray when I export from Flash?